Did Joe Calzaghe really ruin Lacy?

I have seen this statement all over boxingscene for a long time. However I think its important to mention that Jeff "LEFT HOOK" Lacy had a torn rotator cuff in his left shoulder. Now I can tell you that a torn rotator cuff will do great damage to a guys "left hook" and mental ability to use the left in general. I just cant understand why so many people fail to see that this guy PHYSICALLY damaged his most important weapon in the ring, and choose to attribute his recent lacluster performances to some unseen mental weakness after his first loss. That being said War TAYLOR.