I understand that. I've never defended the move. I was more arguing his point that hitting coaches should be Rod Carew types when that's clearly not the case.
I'm going to have to agree with Senser as well, and point out that you missed his point. He's not saying that all hitting coaches are Rod Carew types. He's saying that if you're going to hire a former superstar hitter as a hitting coach, you probably should hire a Rod Carew type over a Mark McGwire type. For some reason you took the Rod Carew comparison far too literally. I think that Senser realizes that most coaches weren't superstar players (as he even illustrates in his point that more average players have to learn the subtleties of the game, thus making them more effective coaches).
So, in summation, I'm not sure what you're arguing about. You agree that it's a terrible hire, yet you're caught up on a Rod Carew/Mark McGwire comparison, when you essentially agree with Senser overall.