Yes, you measure by pre-cooked weight.
Vegetable fat is fine, it's what I've been eating myself for awhile, since I don't eat much meat. I supplement with coconut oil, 2 tablespoon daily.
A binge once in awhile is not going to kill you. Having added muscle mass doesn't do very much to negate the effect of the binge since muscle burns more calories but not significantly more. We're talking about an extra 1-200 calories a day maybe. Cheating once in awhile is fine, don't worry too much about it.
F 28/5'4/100 lbs
"I'm not a psychopath, I'm a high-functioning sociopath; do your research."