"Now as I understand it, Pete can be difficult and stubborn."

Sounds like mis-information. While I do not know him as well as others, I've never heard anyone call him "difficult" or "stubborn" before. If anything, he is perhaps the one individual that I've ever met that best exemplifies the principles of getting people to work together. He has opinions and lives his life based on his morals, but he always puts himself in the other persons shoes and that helps him understand issues and how to reach people.

What you saw in that film was the real Pete Seeger. He walks the walk.