why not ? Serious question or dont you think he will be a good coach.
I don't know whether he'll be a good coach or not, but I suspect he'll find it difficult to transmit his ideas - although a pure manager job, with a good coach beside him, will probably suit him.
But being a player-coach is bloody tough, and you offer little as a coach because you still have to train, you still want to play, and you think like a player. The Giggs experiment is failing miserably at United, and Rodgers' staff is more than qualified and experienced to help our players along. Having someone inexperienced coming in will only fail, I think. He'll be left doing nothing but dropping cones, while the actual coaches work with the team.
I'm actually going through this right now, working with a player-coach. Their knowledge of the game is fantastic, and the little key points they make are brilliant. But they always want to play in the small sided games, and they always want to fix too much. They also can't grasp that what was easy for them, isn't always easy for every other player. That's why people like Gerrard, Carragher, etc., should always start the coaching ladder with kids, because you learn to accept the players for what they are, rather than what you expect them to be.