I think I'm going to go for it, but I have decided to hold myself to VERY strict time limits. My question about alternate forms of transportation (monorail, boat (from MGM to EPCOT via a connecting hotel?)) are whether or not they are more like to screw me out of time or not. I was originally planning to try to take a bus, a monorail, a boat, and the ferry to Magic Kingdom, but I thought I'd be busy enough.
Realistically, even for a crowded day, I think with the help of EMH I can be out of MGM by 10, so that is what I'm setting for myself and I'm dropping Indiana Jones. After that, onward to EPCOT. I'm now considering dropping both of the rides in World Showcase that I planned to do. I'd like to (although I know I probably won't unless I get lucky with Single Rider/Fastpass/short Standy for whatever reason) be out of this park by 12, but I'm giving myself till 1. Then to Magic Kingdom. I'll give myself till 5 here, since it's probably going to require the most time. Finally, Animal Kingdom until 7:30-ish, and I just hope that wherever we agree to meet for dinner isn't too far away or it might make things hard.
I'd like to say thanks for all the help I've gotten so far.