You could however still play D&D as a skirmish game using wandering encounter tables. While I wouldn't recommend using 1e as a tactical skirmish game (because it would get really redundent), 1e is well suited to generating random encounters.
I'd say that before 4e, there'd not be much point in that, but 4e would probably play decently as a skirmish game. The monsters are fairly simple and don't require alot of DM tactical mastery to use well, so its less of a problem having the NPC's controled by someone who has a vested interest in seeing the monster 'do badly'. Tactics with monster are usually pretty straight forward compared to 3e, for example, because the monsters usually have one obvious trick and one obvious board position that they are trying to maintain. (Compare with a 3e Noble Salamander or most outsiders (barbed devil for example) with their varied array of possible tactics and long list of powers.) And, 4e can kill alot of time with tactical play and the whole encounter system supports stand alone meaningless encounters alot better than any prior edition.
(. . .)
I guess that depends on how interesting the players find tactical skirmish games. Alot of people are complaining about how boring and repetitive 4e combat is in the context of a full fledged story line, so while 4e might be my edition choice for a tactical skirmish game I'm not sure that even then it's got enough to maintain interest in combat for combat's sake. However, I remember meeting junior high kids back in the day who had level up characters to high levels simply by picking entries in the MM, rolling up an encounter, and then fighting them, with no real 'DM' required, so I imagine some people would dig it.
The Strategic Review #1 featured a system for solo dungeon adventures, which was included in the 1st ed. AD&D DMG. It's basically an expansion (mainly with map-generating algorithms) of the tables in the original D&D set that mostly have analogs in later Basic sets. One suggested addition was to have a friend write up some special rooms and seal the descriptions in envelopes.
One could also use the rules for wilderness expeditions (including random terrain generation in the DMG, iirc). The original set suggested using the map board from The Avalon Hill Game Company's Outdoor Survival game, but almost any hex-gridded map of suitable terrain could do; the main thing is to decide which hexes are castles and towns. For excursions in the latter, the DMG encounter tables are again handy -- and so is Cities from Midkemia Press (if you have it).
Kellri's Dungeon Designer's Netbook #4 (Encounters) is generally useful.
Just about anything of that sort, meant as an aid to the DM, can be helpful when effectively serving as one's own DM.
you'd have to set up some of those round-by-round preset actions for the more complex creatures, perhaps.
XRP has a book on DMless D&D. I don't recall much about it becuase it wasn't anything I was interested in. But DMless D&D should be possible with a group of fair players.
Word Mill Games has a little something called Mythic RPG which is touted as allowing for GM-less play. One part of this line, the Mythic Game Master Emulator seems to be an excerpt of this system designed to supplement any RPG.
Oh, I don't have any experience with mythic, so please take this with a grain of salt.
I wasn't able to locate that. Do you (or anyone) have a link, please?
The description says said:"Have you and your friends ever sat around the gaming table wanting an exciting, perilous dungeon adventure but no one wanted to be the Gamemaster? Do you find yourself with little time to read through lengthy adventure modules and memorize them? Do you want to get down into the dungeon as quickly as possible and start killing monsters and finding treasure? Then look no farther than Unbound Adventures!
This module includes 20 pages of rules for roleplaying without a GM. Crafted for any number of players of all levels, Unbound Adventures is a masterful resource for adventure and exploration!"