But the bulk of the D&D customers out there aren't convention goers, and aren't optimizers, and aren't interested in a very complex game. A complex game is about as far as most casual players are willing to go.
I participated in Encounters from the second season on, through the playtest. It was almost all casual players and many of them new players. They both thrived on 4e. Players went from never having seen D&D before in one season, to running a table the next. I rarely saw a new player that didn't return for most of the rest of the season they started with. Many spun off home groups. Meetup drew a surprising number of folks in.
Thing is, the bulk of D&D players aren't the new players trying it each year, nor the causal ones playing now & then. There the one's who started playing anywhere in the preceding 30-40 years, and kept with it.
The issue was never complexity, it was familiarity.
A game that's clear & consistent doesn't seem complex when you're learning it, the complexity becomes depth as you get into it.
A game that's unfamiliar, though, seems complex when you're un-learning & re-learning it, there's more to that than just learning it cold, and there's a frustration factor, because you've rolled revs before and it was never this hard...
But the issue with resting remains the same, it's rigid and yet vague, specifically because it's up to each group to determine what type of game they want. They gave a couple of variations, which are actually similar to earlier editions. But they don't work for everybody either.
There's nothing vague about the issue with resting. The guideline is 6-8 encounters/2-3 short rests between long rests. Not vague. The time it takes to rest is 1 hr for short (no limit), 8 hours for long (1/day). Not vague. The balance and the balancing mechanism are positively 'rigid.'
I suppose what's vague about the kind of game you want is that if you want a balanced game, you're locked into the rigid formula, if you want a game of caster superiority, you go with more rests, if you want a grueling down-to-the-last-hp slog, you go 12+ encounters between rests.
If you don't care about balance, of course, you play at whatever pacing you want.
What's not so rigid and a lot more open to style & variation is the range of pacing options the DM might want to use /even within a in a single campaign/, and the options open to the party to rest when they want to, not when it aligns with the balance guidelines. That's the Elephant. A game meant to be flexible, intended that way, with fragile/rigid class balance turning on one mechanism, that, almost uniquely among 5e mechanisms, is not by default completely under the DM's control.
Why didn't this seem to be a problem in AD&D and earlier?
It's just the 5MWD viewed from a slightly different perspective, it was absolutely an issue in AD&D.
Maybe it didn't 'seem' to be a problem because frequent resting at low level was necessary just for hps, and casters were at the low end of their curve then, so the boost they got just helped them keep up? At higher levels, casters ruled anyway, so there was no balance to maintain.
And yet I don't recall this becoming a problem until much later. Is it just because every class has some short and/or long rest abilities?
No, that makes it slightly less of a problem. In 4e, every class had very nearly the same number/proportion of encounter & daily abilities, and it was a non-issue in terms of class balance, the 5MWD only mattered to encounter difficulty. In 5e, the fighter having two specific 1/short rest abilities isn't much compared to the versatility of spells or the number of slots caster get, but it's something he can nova with, even on a 5MWD. By the same token, full casters have scaling at-will cantrips, so in a very long day, they're not at a complete loss, even if they do start underperforming, eventually.
Huh?
Early D&D featured players competing for treasure and XP. It featured tournament competitions in which teams of players competed to be the one who did the best job of beating the dungeon. The introduction to ToH has Gygax telling us that he built the dungeon to defeat certain hyper-competitive and over-confident players.
Early D&D was extremely competitive. The idea that it's not a competition, that there's no "winning" or "losing", and that the point of the game on the player side is simply to enjoy "being" the PC in the GM's gameworld, didn't become ubiquitous in the published texts until 2nd ed AD&D (though you can see it emerging in some modules and rulebooks from the early 80s).
It baffles me that some posters find [MENTION=54380]shoak1[/MENTION]'s approach to D&D strange, when it seems like pretty straightforward, relatively hardcore beat-the-dungeon D&D.
I remember there being something of a generation gap, back in the day. There were older guys (younger than I am now, but they sure seemed old) who played wargames but also D&D, and there were young kids who just started playing Basic D&D with no background in the hobby at all.
I was one of the kids, and that everyone else playing D&D with me didn't have to lose for me to 'win' did strike me as quite special - compared to the 'family' board games and chess I was used to.