Thanks for all the responses... Brian feel free to hijack and compliment anytime. I will pass this on to my Dad.
I wanted to clarify that Eric did not have IMRT. We looked into it, but given the area the radiation oncologist wanted to cover they didn't believe IMRT would be the most effective choice. Eric took Amisfostine and completed about 90% of the suggested doses. This was prescribed to potentially help him regain some saliva. I keep telling him it is early yet, and I will let people know if some saliva returns. So far nothing has happened, but I suspect until a few years have gone by he really won't know the results.
Anyway it was wonderful to read the replies and hear from some of you who have helped so much. And as Joanna said, for the benefit of those reading along, it does get better. It is just a really long, slow recovery process. Six month post radiation I can truthfully say Eric's cancer is still a significant part of his life but is ISN'T his life anymore. Somewhere in the last few months his life of friends, work, recreation, spirituality, etc. started to balance out the huge specter of cancer. From his diagnosis until a few months ago Eric's life was cancer. Fortunately that is changing and cancer is slowly taking a back seat to life again. It is a much better place to be than the dark days of radiation.