Hello PSU,
The reason why doctors have you do this sort of diet is to help shrink the liver (fatty) so it makes it easier for the doctor during surgery to place the band.
Every doctor is different. I did not have to do the pre-op diet. My doc said to enjoy and eat what I wanted until 12 midnight the night before surgery...so I did.
I do know a few folks who had to do the pre-op diet and did cheat... but not on junk. What they did was eat some low fat protein such as chicken, fish. Not alot but enuf to hold them over and not every day.
I'm not telling you to do this, because IMHO we should stick to what our doctors prescribe...its for our own good, so you might want to call him and ask if you can have some fish or ckn.
Good luck