Ilbranteloth
Explorer
The point is to acknowledge how different stories require different resting frequencies.
When you trek through a desert, trying to find the next oasis, having 6-8 encounters a day is not appropriate. 6-8 encounters in total (the entire desert trek) might be more realistic, given the emptiness of arid sand and stone.
And so this wilderness/travel adventure should be empowered to say you are not allowed any long rest at all (except by giving up and returning from whence you came).
Then, the same party of heroes finally find the long-lost City of Sand in the middle of this desert. This adventure is an action-filled dungeon romp with lots of undead monsters and construct guardians, and so a long rest is definitely needed when they reach the City.
But what's more, there's a lot of monsters in this dungeon, and the adventure recommends 5 minute short rests and 1 hour long rests, to keep up the action.
This way the exact same adventurer (same world, same campaign, same PC) goes from "not a long rest in a month" to "four long rests today, and the mummies keep pouring out of the catacombs".
While you could ask for a DMG that allows this, a more realistic hope would be a PHB/DMG that simply says "in the end, rest frequency is up to the adventure author".
Hence us talking about this stuff being in the adventure, rather than the DMG
Thank you for being one of the few that can acknowledge that your favorite game isn't flawless and could be improved further
What I want is an edition of Dungeons & Dragons that acknowledges that this is a problem for some DMs and scenarios.
What I want is an edition of the PHB and DMG that doesn't tell the players in no uncertain terms "have an hour - you can count on getting your rest". The default assumption should be to defer to the DM and scenario how and if resting works.
I hate being a DM that takes away stuff the PHB gives out. I'd much rather the PHB didn't give it out in the first place.
So thanks, but no, I don't want a grittier system... and I definitely don't want another non-D&D system
OK, so you are addressing several different things in these posts. But to start with, I totally disagree that different stories require different resting frequencies. Resting should almost never be part of the design of an adventure. And the rules for resting certainly shouldn't change from adventure to adventure. You've decided that they don't get to rest in the desert - not because of any meaningful aspect of the fiction, you just don't like it. But that first encounter ended up being much more deadly than you expected because of some bad tactics and bad die rolls. Now what? You've changed the rules and said they can't rest at all. Not a good solution. Something like the rules for resting should be consistent.
First, this is nothing new
The first is the suggestion that a campaign should have different resting rules. Tournament have had something like that in the past - the one I recall is A4 - In the Dungeons of the Slave Lords (1981):
"Resting: Characters may decide at some point to rest and/or sleep, particularly in order to regain clerical spells. There are several ways to dissuade them from this. One way is to tell the players, “You rest for 40 minutes but then there is an earth tremor, slightly larger than the last. Your rest is spoiled.”The best way to deal with this in a time-important situation such as a tournament is to have the characters’ rest time equal real time. To do this, the DM simply leans back and does nothing, responding to hurry-up exhortations with, “You’re still resting.” Most parties will catch on within a minute or two and give up on this particular ploy."
Why is resting a ploy?
So let's look at your desert example: You want attrition to be a thing, so that later encounters are harder than earlier ones. OK. So they're in a desert. They have to get water or they'll start taking damage. Oh, wait, there's a spell for that. You can't put a time pressure in play for that. OK, how about the heat? Well, not only are there spells that help, but the rule is written in such a way that as long as they have water (which they do), they don't have to worry about the heat. Wandering monsters? Oh right, you didn't want that. What possible reason can we come up with that will prevent the party from resting when I don't want them to - oh I have it!
Because I said so.
--
It's not a problem
There's a difference between a design that's a problem, and a design you don't like. I have pretty much rewritten the entire PHB because I think level advancement is way too fast, there are too many superhero style abilities, and it also includes changing the rest/recovery system too. Because 5e as a whole is designed to empower the PCs, to be easier overall. I don't like that. So I change it. But that's not a "problem" - the game wasn't designed for me.
Sure they can be killed, but it's not likely. You want an edition that acknowledges that the resting mechanic is a "problem" - I think it already does that. That's exactly why the DMG has alternative options - because they're acknowledging that the default design isn't for everybody. You just don't like any of their solutions.
The problem is, that any answer other than the players doing what's right isn't a good one. When the game is designed around limited use abilities, there's a method to recover those abilities. In AD&D memorizing spells took a long time. The expectation was that you were essentially memorizing spells for the entire adventure. Not many people followed those rules though. You just got them back the next day. But there wasn't anything then stopping you from just parking there and waiting either.
In your desert example, or really any example where you intend to have a small number of encounters, means that they will always be at full power, or close to it, for each encounter. In order to change that, you don't need to change the resting and recover rules, you need to have additional ways to drain their resources than combat.
Whether the rule is written in the PHB or not, anything that changes the consistency of the recovery rules during the adventure will seem unfair, and not make sense within the fiction either. The only thing to prevent the PCs from saying, "we wait here until we're full strength" is the players themselves.
Even if you use the gritty rules, and say a long rest is a week of rest - they'll still do it if it's important enough to them to be at full strength. In AD&D, if you actually enforced the spell memorization rules (which took a long time), the rest of the party had to agree to wait for a day for the wizard to have all their spells again. Most of the time they told the wizard to suck it up. But when every class benefits from taking a rest, then it's different.
What's the real problem?
This is an inherent problem with this type of design. Think of the video games that use similar recharge mechanics. A lot of times you back out of combat to run around in circles to get your abilities back. It's absurd. But that's the way people play. Because they treat the characters like pawns in a game, rather than real people.
The problem I've had with 5e in general is that it's designed to skip the "boring" stuff. Not as much as 4e but it is. Anything that hinders the PCs from their next (super)heroic encounter. So a long rest can be interrupted, but you have to be interrupted for a full hour. Combat typically takes about 30 seconds of in-world time. So you can go to sleep (or not, as we know you don't have to sleep to get the benefits of a long rest), and be literally be awakened 119 times during the night for 30 second-long combats and still benefit from the long rest.
The design is based, in part, on guidelines like, "penalties aren't fun," and "not being able to use your abilities is not fun," and "tracking resources is not fun," and "having one class with healing abilities is not fun," and "players will stop adventuring and wait to get back to full strength, or near full strength," etc.
Really, there are so many things that were designed to take away things that weren't fun, they've ended up taking away the fun. Because what's fun is a challenge to overcome.
--
Solutions
1. Introduce rules that address things like sleeping in armor. If they have to be out of armor to rest, it really alters their approach in threatened situations. This provides a risk/reward scenario. "I can recover abilities and hit points, but if something attacks in the meantime, I'm screwed." Of course the armor thing is trivial at 5th level as soon as somebody gets Leomund's Tiny Hut (another spell altered to "skip the boring stuff").
Of course, we track ammunition, encumbrance is a thing, food and water too (even though magic can trivialize these things). Actually, the ritual rules, and the increased potency of cantrips (which started in 3e) is another huge factor in managing resources. Again, it goes back to making it easy for the PCs. "Because nobody would pick those spells because fireball is better."
That's true if your life is nothing but combat. Oh, wait, it is, because we skip the boring stuff.
But if you actually have to expend spell slots to manage the stuff that takes up 90% of the adventurer's day, and still have spells left for the combat (10% of the day), it has a big impact on play. For example, when you had to choose between magic missile or light, you might bring a torch or a lantern. But once you ran out of torches, your wizard has to use one of their two spells for the day for light. So I alter a lot of spells, and I completely control access to spells (after 1st level wizards don't pick their own, they get what they find along the way), at least arcane ones (and bards use arcane spells and spellbooks in my campaign), to prevent too many of the "easy" solutions.
2. Fictional elements like nightmares are another possibility, or a desecrated/cursed/evil locale that prevents them from benefitting from a long rest no matter how hard they try. But you can only use this so often.
3. One mechanical option that isn't in the DMG is to use gritty realism approach for hit points, and the normal resting rules for everything else. That at least addresses the hit point side of the equation. That works if the issue is hit points. I still think magical healing needs to be reduced for this to make much of a difference, though.
4. My primary solution has been a totally different approach. I don't attempt to take away their recovery of abilities, nor do I alter the rate of healing. Instead, I use the Exhaustion rule as a model to introduce penalties that reduce the effectiveness of their abilities. And many of these are long term.
For example, critical hits and falling, among other things, can cause injuries. It uses the exhaustion track, and recovery uses the death save mechanic. You get one death save at the end of a long rest. So it takes many days to recover from an injury. But it also required changing healing magic so they couldn't just use that to get rid of it.
I have three levels of fatigue - overexertion, fatigue, and exhaustion. All use the same track, but overexertion is recovered after 10 minutes of resting, fatigue 1 hour, and exhaustion takes 6 - 8 hours of sleep. All require sufficient food and water. If more than one effect is in play, you suffer the effects of the worst condition at the time (level 1, level 3, etc.), and they are recovered independently.
My penalties are a bit different too:
1. -1 on ability checks, attacks, and saving throws, can't take bonus actions. The penalty increases by 1 for each level.
2. Speed halved, can't take reactions.
3. Hit Point Maximum halved
4. Impaired*
5. Stunned
6. Unconscious, dying, or something else depending on the condition.
Overexertion only goes to level 4, then you start taking fatigue, up to level 4, then exhaustion.
Impaired
• Whenever you make a decision, you must make a Wisdom saving throw with disadvantage. Failure indicates you make a poor choice.
• To cast or maintain a spell, you must roll on the Wild Magic Surge table with disadvantage.
There's a good chance that somebody's not at 100% in the group, and that they can't easily do anything about it.
--
I've actually been putting together a comparison of Tomb of Horrors 1e vs 5e. And the 5e rules make a significant part of the adventure trivial. The only thing that's harder (significantly so) is Acererak himself. Resting is one of the main reasons, although the reality is, that's just a factor of time. There's really nothing preventing you from resting for a week or longer in the tomb if you wanted to. An interesting thing about the design is that there are a few key points where it specifically (by design in my opinion) forces you to take a rest and regroup so you'll be able to survive. At least some of you...
That's the nature of the design of the game itself. The focus is on empowering the players, making it easy, and making it "fun" as in "not boring" and certainly not in limiting their resources.
My point is, your complaint about the ability to control rests is misguided and has always been a potential issue. Players will rest when and where they want. The issue is in the design of the game as a whole - it's really not built on a concept of attrition and resource management, and if that's what you want you either have to use the "because I said so" approach, get the players to agree not to game the system, change the system, or live with it.
For me, the 5e mechanics are fantastic. As a long-term DM/player, it's trivial to me to adjudicate/modify the rules as needed, and since I have a lot of new players in my campaign, I can teach them to play AD&D with better mechanics. So these don't become issues. But, I also recognize that some players prefer a better understanding on how things work. So I write house rules so everybody has access. But in the end, in my opinion, it's a mix of play style - we're going to adventure, and we'll take a rest when it makes sense (like, lunch, unless we're really hurt), and tweaking the rules to get the end result you're looking for. In OD&D/AD&D era the expectation was that the rules would be modified. Stuff dropped, stuff added, etc. The PHB and 5e in general is pretty good about saying that the DM is in charge of the rules, and what he says goes. It gets muddied a bit with certain rules being labeled as optional, since it implies the other rules are not. But they are all optional, and players need to understand that the DM is responsible for making sure the rules work to support the setting and adventures they want to run. I still don't think the solution is changing the way resting works from adventure to adventure. But as the DM, that's your prerogative, and the players need to understand that.
Nothing about this should come as a surprise to the players or their heroes. Everything about this should be known beforehand. 
