We've recently converted our D&D campaign to 1st Edition AD&D, and one of the questions is whether we should use Weapon Specialization. Specialization was published in Unearthed Arcana, and is presented as an optional rule in OSRIC. It was certainly carried over into 2E and beyond through feats.
Specialization beefs up the fighter quite a bit, if you think they need a patch; +1 to hit, +2 damage, and extra attacks.
Without specialization, fighters are free to pick up most weapons and use them equally well (unless you're using proficiency slots, which limits the pool a bit). Once specialization is introduced, the fighters tend to use only their specialized weapon for the rest of the game (reducing overall choice). Most everyone picks longsword.
Previously, we were using a "weapon-by-class" house rule that gave the fighters equal damage regardless of weapon, and that was pretty awesome, fighters ended up using all sorts of weapons and were much more opportunistic. But all house rules have been repealed since we've converted to AD&D to level set again. One of my goals with this AD&D experiment is to try and play as By-the-Book as possible*. Allowing weapon specialization would probably be the first house rule.
Let me know how you feel about 1st edition's Weapon Specialization. It seems like a good time for a new poll, too.
*So far, we've only had two problems to discuss. In Labyrinth Lord and the Advanced Edition Companion, alignment restrictions on the paladin's companions are looser, and so a druid henchman was introduced by one of the other players. An AD&D paladin, by-the-book , won't support a Neutral NPC in the party long term. Our house rule will be that as long as the party's quests are supporting Law and Good, the paladin will accept the presence of the druid as a contributor on those quests.
The other one is the awesome BX Staff of Healing, which doesn't exist in AD&D. We're using it "as is". The AD&D Staff of Curing is significantly different.