I tried logrolling one time when I was visiting a friend in Oregon, and it is every bit as hard as it looks. Just standing up on the log was a major challenge for me. The other guy was a little better at it, so he started walking at a very slow pace and let me catch up. I could see why the real logroller competitors watch each other's feet. If the other guy suddenly changed direction, I'd better be prepared for it.
I'll say one other thing about logrolling. Those falls start to really hurt after a while. I was really sore the next morning after twisting my ankle twice and falling hard on the dock once.