Condensing this down: Yes, passive Perception applies often as you say... until it doesn't.
According to JC, it's always on, which is more than often, but I will grant that this is an exception-based system, so there will be exception, therefore rare, and therefore not a reason to make general changes.
The rules carve out when it doesn't and those have been posted by
@Seramus upthread.
Once more, no, they don't. You insist on reading them in a specific way, but I have shown you that they say nothing of the kind. I have demonstrated this to you, and once more, you choose to ignore it. Simply read the rules and see that it's not because you are mapping now and then that you lose your passive perception. Nothing says this. Otherwise, once more, prove it, but I remind you that, so far, you have been wrong 100% of the time on rule interpretation and on the RAI.
You seem to be ignoring this in play, so far as I can tell, and doing so means Perception is overvalued.
I am ignoring this because not only as these rare cases and exceptions, but on top of it, your reading of the rule is flawed. So yes, I am ignoring an improper evaluation of the the value of perception.
If you're also not taking marching order and other context into effect, which the DM is empowered to do by the rules, you're further making Perception better than may be intended. In such a situation, I would fully expect every player to take Perception and Observant and ask to have a pet to grant advantage. This would not be abuse, but simply playing the game as you have presented it. But for your seeming social agreement around optimization, I'd be surprised if they didn't.
They don't because even with the value of perception described by the rules, it's not that critical in the type of adventures that we run. A clever player will not be surprised just because his perception is low, because he will get advantage or even automatic success for immersing himself in the world, anticipating what is going to happen in the world and taking the appropriate (counter)measures.
In the context of how I run it, you're surprised if you put yourself in the position to be surprised and something tries to surprise you.
And sometimes, you will be surprised because some adversaries are good at that.
If a character is performing one of the listed travel tasks (which all have useful benefits in my game), they are automatically surprised if a stealthy monster comes calling.
No. Once more, this is not the way the section reads. You absolutely want it to read that way, but please give me the sentence that says that if one is doing a bit of mapping along the way, he forsakes all rights to passive perception. It simply does not exist.
That is the risk they are taking if they turn their attention away from keeping watch for danger and, hopefully, the payoff is worth the risk. I have it where searching for secret doors while traveling the adventure location is at least as distracting as these other travel tasks since, as you point out, the DM can decide this.
And once more, you are confusing deliberate searching (which for me is more investigation) with simple passive perception.
It should be noted, however, that not every monster attempts to surprise the party. Per the rules governing surprise, the DM makes this determination. For my part, only monsters trained in Stealth and/or who have some kind of lore indicating a preference for ambushes will try.
You do what you want in your campaigns, I will roleplay the monsters in my campaign the way I want. Unless a monster is extremely stupid, achieving surprise is actually the base technique in most of the animal kingdom. I have even personally tried (and succeeded) in achieving surprise while wearing full scale armor at night, just needed to prevent some banging between my hauberk and my leg armor. Some might be more successful than others, but once more, you are reading the section on surprise wrong. It's a dangerous world out there, and by default, even more than being trained in perception, creatures will try to be quiet unless they are very stupid, and the surprise rules reflect this. By default, surprise is checked as perception vs. stealth in EVERY combat. In some combats, obviously, there will be auto-success and failure, but it's not optional.
COMBAT STEP-BY-STEP
1. Determine surprise. The DM determines whether anyone involved in the combat encounter is surprised.
That's about a third of all monsters, I'm told, though that may not apply to all terrain types equally (e.g. Underdark monsters might be sneakier in general than desert monsters). The players will have to take this into account when making their meaningful decisions during play. It simply isn't enough to max out Perception and call it good because the DM rules that passive Perception is always on no matter what decisions you make.
I never said that, actually. I just said that it's always on. After that, of course, nothing prevents you from being clever.
As well, traps the party are approaching can only be noticed by the front rank of the marching order.
Once more, where is the rule on this. I'm sorry, but as usual, you are interpreting things, and that is just totally inappropriate. SOME traps, in SOME circumstances, might only be noticed by the characters in front, but that is a purely local ruling from the DM based on circumstances. It's not a rule. And when people are 5 feet apart, it certainly, on average, gives enough visibility for people to notice things in front, and even more to the side or up. Once more, the advice is only "The DM might decide that a threat can be noticed only by characters in a particular rank." It's not even the front rank, and the general rule just says "Use the passive Wisdom (
Perception) scores of the characters to determine whether anyone in the group notices a hidden threat.". So once, more, it's always on, for everyone unless the DM makes a specific ruling. And although you seem to absolutely want to have these restrictions in your campaign:
- Don't tell anyone that they're not playing by the rules if they don't.
- Don't tell anyone that they are doing things wrong if they dont't.
Neither is justified, and it starts smelling a bit too much of badwrongfun.
So if you put the Observant character up front, they stand a good chance of finding those traps before the party runs afoul of them. However, that Observant character might not be the most heavily armored person in the party and attacks coming at the party from the front will tend to target them first. (People in the middle and back ranks have the benefit of cover!) So there's some risk there for the player to consider.
Don't worry, most players are not stupid, and they are able to make such judgment calls, including sending scouts, having someone up ahead which is probably not the most armoured for stealth purpose, etc.
And also, despite what you might think, in a dangerous environment, people don't just walk there with their head in the cloud, or reading a book, or writing in it. Even the mapper will only do that in secure locations, for example.
Now, for long overland exploration, as mentioned, we have used the rules for hexcrawling, resource gathering, mapping, etc. But once more, these have been used ONCE in what, 8 years of campaigning 2 campaigns in parallel. So it's hardly a common case.
Now enter our ranger: They can do a travel task and keep watch at the same time in their favored terrain. Which is pretty neat.
And I thought they were underpowered, now I'm reassured.
What this means is that, in my game, Perception is useful, but it's not an auto-win button.
Never said it was, but for me it's way easier to control the fact that bonuses stay within a reasonable range, especially in 5e because of bounded accuracy. That way, people who have it have an edge, but it's NOT an autowin button. Whereas allowing the use of a wolf to get a constant +5 on top of observant IS an autowin button, and that causes problems.
You need to do things in the game to put it to use and that will come at the cost of not doing other things and additional risks. This is fully within the rules and eliminates the problem a lot of people seem to have with Perception being overvalued.
And I find your solution useless, as my expectation is that characters are seasoned adventurers and not idiots, who would not walk down a dungeon corridor doing anything else than being aware of danger and taking precautions. And probably being generally stealthy too. I have done hundreds of LARPs, and I can tell you that unless you're relaxing in a tavern, your passive perception is always on, and you are always trying to be stealthy. Whether you succeed or not depends on your actual capabilities, but it's always better than not being careful, which only idiots do.
And once more supposing that characters are idiots and that they would be doing activities that would prevent them from noticing threats as best as they can in a dangerous situation is not only derogatory for the players, but it's also extremely biased towards certain profiles. That's not my preferred way of running campaigns.