I'll sign it!!!!
As far as the jet boat seat position...when I first got my jet boat, a friend told me that I shouldn't have a high back seat because if I ever hit something, I would get thrown out of the boat very easily. Well, because I have a high back seat I can see from a better angle and (knock on wood) I've never been thrown out of my boat while running the big motor. I have been thrown out a couple of times while drifting when my trolling motor hit a log (ask Jeremy). My buddy who told me that, however, sits in his console seat and has been thrown out at least 3 times that I know of.
As far as the ability to run shallow...I think weight distribution is very important. I, like Al, have an open middle in my boat. I tell the rider in my boat to sit on a cooler so he can kind of adjust his location to suit the situation. It seems to me that if we both sit in the back, I can go a couple of miles per hour faster, but if he sits on a cooler, a little closer to the front of the boat, we can't go as fast, but can go maybe 1" or so shallower. I could be wrong, but that's my guess.