Interesting article.
Took my DD to a tryout recently. Coach was one of those "good job" all the time guys. He also did the da da da sports center thing when a player made any nice play. Very encouraging type guy. We got back to the car and I asked her what did she think. She said "that guy is a rec ball coach, he talks too much, he says good job even when they miss the ball. How would I know if I did something wrong?"
I find the serious coach says less, that just has an aura of high expectations about him is what my DD responds to best. The coach that you don't want to screw up in front of and definitely don't want to be caught not paying attention to instruction. Thats not me (yet) I talk too much. LOL