During the flurry of postings to our Busan D&D Facebook page, and some KakaoTalk between Jeremy and myself, there was a brief discussion of whether or not old school D&D should use a "rest mechanic" similar to 4E (and apparently, I stopped checking the updates, D&D Next).
For those unfamiliar, in 4E they break 'rests' down into Short Rests and Long Rests. In a Short Rest (5 minutes or so), characters can spend their Healing Surges (limited per day) to recover hit points. All "encounter powers" also refresh. In a Long Rest (8 hours), all damage is recovered, all healing surges are refreshed, and all encounter and daily powers are refreshed.
I mentioned to Jeremy that there already is a rest mechanic in Classic D&D/AD&D. It's called going back to town. He thought I was being snide at first, I think. But it's that simple. If you want to get hit points back, and spells back, when you're playing in a dungeon setting, retreating from the dungeon and returning later is the way to do that. Sure, you can camp in the dungeon/wilderness (in Ur, we often do that). That gets some hit points back, and all spells. But if time is not of the essence (and unless you're running a tournament module or a Dragonlance style adventure path it may not be), then town is the smart way to do it.
Back when I ran some sessions of D&D at our old Board Game Group, that bugged the crap out of Alex. Josh had a Fighter and a Magic-User with Sleep. Alex had a Fighter and a Thief. They went into the dungeon, ran into kobolds, say, and the M-U cast sleep, the Fighters took care of any unaffected, and then the Thief would look for traps, treasure. With that one monster encounter finished, Josh would then say he wanted to go back to town to rest. And unless they ran into undead where sleep didn't work, every time he would want to do this. As a DM, it didn't bother me. I was able to plausibly bring in reinforcements or think about how the kobolds or goblins would react to the loss of that patrol. The players got to take on each combat at full strength, but at the cost of having an enemy prepared for them later on. Alex hated it. He was interested in covering territory and getting a sense of progress. Josh was interested in surviving to second level.
For me, that's the essence of the strategic/tactical play needed in RPGs. 4E style rest mechanics seem like a way for players to have their cake and eat it too. There's no need to make the tough decision to go back to town and risk having enemies prepared for you versus pressing on and facing the unknown at less than full strength (or darn near it). And that, Jeremy, if you're reading, is why I will not be using a modern "rest mechanic" in my games.