How long can you watch this?

Why is there someone in the back coaching them along the way, like they're in 4th grade?  I stopped watching at 1:41.

I don't want anyone to think this isn't related to the Celtics either.  In my quest to find out what the hell's happened to the more obscure Celtics, I stumbled upon this video in my search for Bobby Wilson.  I don't think that's Bobby Wilson who played for the Celtics in the 70s.