Long story short my friend played for him and mentioned how he's difficult. Like if you don't have chemistry with a player and it's based on skill-set, an example being a guy like Kessel couldn't play with Crosby or Malkin, but played better with Bonino and Hagelin. If a guy like Kessel/Crosby/Malkin said that he'll basically ignore you or act like he's above you and says how it's his team because he's a head coach as it's a workplace not a place for friends or drama. When in reality that's what it usually is, sure as a manager myself it's a place to work but you don't want as little tension as possible. Once in a while he threatens to try and have you traded or sent to the minors if you don't co-operate.
My prediction with Keefe is he's not going to see eye to eye with how players are rolled out, line-ups, starting goaltenders or certain gameplans.
Honestly, the guy has a good coaching mindset, like I said extremely smart but super stubborn and acts like he's in full control while also expecting people to brown-nose him.