I suspect they were personal reasons; Phil has retired from networking entirely and between battling cancer and turning his remaining time to teaching high-school students about science and engineering, I know he's not interested in AMPRNet anymore. He said so when we had dinner a few weeks ago.
- Brian
I'm sorry to hear that... please send him my best wishes when you have contact with him. It is his work that made the AMPRNet possible in the early days...
Rob