Good thinking! I wouldn't have thought of that `xchg` one in DOCOL, very clever.

I'll futz around with making DOCOL's address as a register and see if I can make that work, though I don't know if that will work since I think some of the mechanisms in place have additional functions.

EDIT: So, I don't think this will work. I'd be using `dx` to store DOCOL's address, but this appears to get clobbered somewhere, fixing which would outweigh the 1 byte benefit you end up actually getting. I'll keep thinking about it though!