but if you granted 1 (e.g., granted that 'a function that takes inequitable distributions of resources between equally deserving agents into equitable distributions thereof' is not a crazy candidate meaning for the English word 'fairness'), would you still disagree with 2 and 3?

If I grant 1, I currently can't think of any objections to 2 and 3 (which doesn't mean that I won't if I took 1 more seriously and therefore had more incentive to look for such objections).

And do you think that morality is unusual in failing 1-style regimentation, or do you think that we'll eventually need to ditch nearly all English-language terms if we are to attain rigor?

I think at a minimum, it's unusually difficult to do 1-style regimentation for morality (and Eliezer himself explained why in Unnatural Categories). I guess one point I'm trying to make is that whatever kind of reasoning we're using to attempt this kind of regimentation is not the same kind of reasoning that we use to think about some logical object after we have regimented it. Does that make sense?