I had a break for about a week after a having just a few IMRT treatments before they changed the radiation field. Also I think that you need a significant radiation dose before you actually fry your glands and I seriously doubt that this happens within just a few days. Also, IMRT is quite good to treat a more diffuse (larger) target and it still allows you to spare certain regions (if you choose to).
Having said this, I echo Davids sentiment. I would listen to the IMRT guys.

M