On Thac0: something about the way my brain works constantly trips me up with descending AC. The PHB didn't do a very good job of teaching me it, and even now that I've learned the trick (subtract to-hit roll from Thac0 to get target AC) it still feels counter-intuitive.
And it's not just me. Some time ago, the idea of running a 2e game came up, since I have a friend who waxes nostalgic for it, and is always going on about how superior it was to modern D&D.
But the other players we roped into it were very confused about the rather arbitrary decisions made with the rules set, and the whole AC system felt strange to them.
Like how a +1 armor lowers your AC, but 17 Dexterity has a -3 defensive adjustment. "Why," one player asked, "aren't these things more consistent? Why do some rules elements expressed as positive integers and others negative?".
Like a +1 sword made sense, even though it effectively lowers your Thac0, it's easy to grasp that it's doing that by adding to your attack roll. But then one guy had a Swashbuckler and he was really hung up on the fact that his Dexterity adjustment was a negative integer and his Kit gave him a +2 to AC at the same time. "This doesn't make any sense!", was the gist of what he was saying.
And I think this is really the point to drive home, I think. If everything worked in the same direction, it wouldn't matter if we used ascending or descending AC. Have low rolls be good on the d20* and have all modifiers subtract- just as easy as it is today.
But rolling high to arrive at a low number seems like this needless step, as does having both positive and negative "bonuses". Now I get, to a lot of gamers who played earlier forms of D&D, this makes perfect sense to them, because they're used to it, but from an outside perspective, it just adds to the arcane, sometimes byzantine nature of AD&D's rules.
*And when we got to NWP's where low rolls are good and high rolls are bad, I watched a player throw a d20 off the table in disgust, lol, as it rolled low when he needed it to roll high and vice versa.
I know that someone is going to instantly take umbrage with my entire post and repeat to me the whole "Thac0 is easy/it's just math/neither me or anyone I ever played D&D with ever had these issues" conga line- it's great that you think this way and it works for you.
But there are people who it doesn't work for. Plus, I mean, has anyone heard a new player complain about ascending AC being hard to grok?**
**(sighs, knowing someone will likely immediately post "yes").
