It's tempting to use Weapon vs. AC Type for our next AD&D foray (into A2, part 2), but how?
Not counting "don't use it at all," I see four options:
Only versus specified armor type.
Basically, use it as written, ignore weapon vs. armor type when it doesn't apply.
Pros: We get to try it out. Some weapons will really benefit in some circumstances.
Cons: Adds a lot of complexity, but only sometimes. Penalizes everyone who doesn't know their weapon vs. armor type well enough to choose targets, or weapons, well. (This applies as a con to all of the below options, as well.
Versus all armor, with an assigned type.
Use it as written against specified armor types, but then assign a "type" to non-specified armors. Enemies with natural DR will get a "type" assigned.
Pros: More widely useful.
Cons: Have to assign an armor "type" to everything.
Versus all armor, by AC.
Ignore armor type, use it versus armor class, and just use it - with everything below AC 2 treated as 2.
Pros: Easiest version. No work, just lookups.
Cons: Penalizes some weapons types pretty much universally. Makes no sense.
Versus worn armor, by AC.
Pretty much like the option before - worn armor only, but use AC.
Pros: Second easiest version. No work, just lookips.
Cons: Penalizes some weapons types pretty much universally. Makes no sense. Requires complexity sometimes.
You'll notice I regard occasional complexity as an issue. Each time a rule sometimes applies, but not always applies, it means we spend a moment checking each case to see if it applies. That takes time even in cases where it doesn't matter.
Overall? I'm still not sure. I'd like to try just to be able to say I did, and to give an actual play assessment of what it brings to the table . . . but it feels like choosing the least-bad option. As a result, I'm still not sure.