I am going with "Nope" because in order for ability score damage to really work as a sub-system of the rules, the following needs to be true:
(1) It needs to be baked into monster statistics at a minimum. So a creature with poison would need to note that it does "X dex/str/whatever" damage from the outset of the system. Switching to an optional corebook for cross-referencing is probably not in the cards.
(2) Likewise, it needs to be baked into the spells, including some we'll almost certainly see early on like Feeblemind and Ray of Enfeeblement.
(3) It makes assumptions about how monsters are built that goes outside what I expect out of a simple monster-building system - namely that ability scores shouldn't directly affect a monster's stats. I don't want them built like a PC; that's an excess I've left behind.
So given all that, I don't think it works as an optional module. Maybe I'm wrong - and I hope so for all the people it's important to.
I think this objection is easy to handle, with a little discipline by the authors. All you need is some evocative keywords, sometimes mixed with some numbers for scaling. This is, in my opinion, how early D&D poison types were intended to work. They just got side-tracked.
So you don't say that a monster with a paralytic poision does 3 points of Str damage or whatever. Rather, you list it as "Paralytic Poison V" or similar.
Then you have modules like this, with an entry for each type and level. Paralytic Poison V might work out to this:
- Simple Narrative - does 3d6 poison damage. If character reduced to zero hit points, becomes paralyzed.
- Simple Grit - character is paralyzed right now.
- Ability damage - character loses 3 points of Str (with Str 0 or less being effectively paralyzed).
- Sim Grit - detailed, semi-realistic/fantastical nerve poison mechanic.
I'm assuming above that the saving throws would be outside the listing and put into the monster stats, as these would be common across listings, but if I'm wrong, they could be embedded into the listings, too.
That might sound like a lot of work, but this isn't like looking up spell listings for an NPC high-level wizard. You don't care about all of those options. If you are doing "Simple Grit", then you only care about those options. You care about the difference between Paralytic Poison V versus the VI version. And you care about the distinctions between Paralytic Poisons and other types of poisons. The whole thing probably fits on a single sheet, and after a few adventures, you've got it mainly memorized.
Not every indirection into a module is complicated in practice.