Philotomy Jurament
First Post
Sometimes, we'd start big fights in taverns just to use the DMG unarmed combat stuff. We looked at it more like a "mini-game" within the game, though. 
The unarmed combat system from Unearthed Arcana was one of the few rules additions/changes that I ended up adopting from that book (although I did use some of the spells and magic items).
As far as the "light/heavy" question goes, I agree it depends on what you're comparing it to. I also agree that AD&D has a modular subsystem based design, which lets you replace or ignore stuff you don't want without major effects on the rest of the system. That contributes to its ability to be played in a "rules light" manner.
The same is true of Original D&D. It's just as "heavy" as AD&D, if you consider the OD&D Supplements and Chainmail. The "lightest" D&D edition is probably B/X (maybe Holmes, if you consider that its own thing, but I tend to lump it in with OD&D). Even BECMI adds a lot of heavier optional subsystems (weapons mastery, general skills, etc).

The unarmed combat system from Unearthed Arcana was one of the few rules additions/changes that I ended up adopting from that book (although I did use some of the spells and magic items).
As far as the "light/heavy" question goes, I agree it depends on what you're comparing it to. I also agree that AD&D has a modular subsystem based design, which lets you replace or ignore stuff you don't want without major effects on the rest of the system. That contributes to its ability to be played in a "rules light" manner.
The same is true of Original D&D. It's just as "heavy" as AD&D, if you consider the OD&D Supplements and Chainmail. The "lightest" D&D edition is probably B/X (maybe Holmes, if you consider that its own thing, but I tend to lump it in with OD&D). Even BECMI adds a lot of heavier optional subsystems (weapons mastery, general skills, etc).