In OD&D, all characters possess six ability scores: Strength, Intelligence, Wisdom, Constitution, Dexterity, and Charisma. Of these six, only the last three have any game mechanical benefit. The first three are all prime requisites, each one tied to one of the game's three classes: Strength for Fighters, Intelligence for Magic-Users, and Wisdom for Clerics. The only benefit these abilities provide is in the form of XP bonuses to members of the class that have that ability as a prime requisite. Thus, a Fighter with an Intelligence of 5 suffers no specific game mechanical penalties, although individual referees might choose to reflect the character's limited mental capacity in various ways. According to the rules, though, having an Intelligence of 5 means nothing unless the character is a Magic-User, in which case he suffers a penalty to earned XP.
Leaving all other issues aside, this system works well enough until Supplement I comes along. Supplement I gives us the Thief class, which uses Dexterity as its prime requisite. Unfortunately, the LBBs had already given Dexterity a game mechanical benefit -- missile accuracy -- meaning that Thieves with high Dexterity gained not only an XP bonus but also a bonus to hit with bows and slings (assuming they could use such weapons; OD&D is non-commital on this point). Furthermore, Supplement I itself gives most of the other abilities additional game mechanical benefits above and beyond being XP boosters for certain classes (Wisdom, oddly, is the exception). Consequently, Supplement I not only increases the importance of ability scores generally but also allows classes to "double dip" when it comes to prime requisites.
Let me say here that I actually like ability scores having some value beyond being XP boosters. I think in the case of the Fighter particularly, it's important that a character gain game mechanical benefits from having above average scores. At the same time, the double dipping aspect bugs me, which makes me think I ought to just ditch the idea of prime requisites and XP bonuses entirely. I haven't yet done that in my Dwimmermount campaign, partially because XP gains are glacial enough as it is that the small bonuses that high prime requisites give serve a useful purpose.
I won't deny that I find the way post-Supplement I OD&D handles ability scores and prime requisites to be infelicitous. Moreso than most mechanics, it feels very "half-baked," as if there were several different goals and intentions present, none of which quite dominates enough to bring some degree of rationality to the whole. Granted, I think over-arching rationality in mechanics is overrated, but I can't shake the feeling that the situation created by Supplement I is untenable and indeed unstable.
I find myself of two minds about the whole thing. Part of me just wants to leave well enough alone and not worry too much about the worrying tendencies I see in OD&D + Supplement I, which make high ability scores ever more important. Any problems that arise can be dealt with on an ad hoc basis and, truthfully, the issues haven't played any real role in my Dwimmermount campaign, so why worry? Another part of me, though, wants to try and tinker with it all so that it finally "makes sense." Yes, I realize that's a Quixotic endeavor for a lot of reasons and probably one that will yield worse results than just letting things be. Still, like many gamers, I'm a tinkerer by nature and seeing something like the mess that is OD&D ability scores, I can hardly resist the temptation to "fix" them.
Anyone else have similar feelings on the matter or am I the lone weirdo here?