Paul, that's an excellent description of the mechanics of the various radiotherapy options. It's good to have such expertise on the forum.
For proton therapy, I thought getting an increased radiation intensity as it traveled, then stopping, was a good thing, but as you pointed out, this means that the tumor border is at a highest intensity (at least on the entry side). I liked the way the "bullet" can be stopped before it exited and therefore spared the healthy tissue the other side of the tumor.
Does the uncertainty as to when the proton releases its energy affect angular accuracy or distance along the path accuracy?
Good point about the middle of the tumor getting toasted with GK, since in the tumor may be the nerve it's growing on.
When is the medical profession going to come up with a treatment for vestibular schwamnomas? Something that improves you rather that creates more havoc.
In your case Paul, it appears that you have had a good outcome. After 7 years how is your hearing going?