Well, for one, we've heard rumblings from posters on this board and from
this post going back a few months now that Walman fell out of favor in the locker room.
We don't know what he did. Maybe the rest of the league does. Obviously if Yzerman didn't have to attach a second to him to get rid of him, he wouldn't have.
Yzerman clearly felt he needed to free up that roster spot from Walman and his cap space in order to improve the team. Let's see what he uses it for before we freak out over losing a mid defenseman.