We've been without a qb coach before. Many teams have.
Yes we have. And one of my pet peeves is that we haven't had a legitimate QB coach on staff since Kavanaugh (not exactly a QB guru either) coached for Buddy.
According to Green, one of Sean's attributes is that "He's played the position." Many successful QB's will tell you that it helps to have someone tutoring you or running the offense who "has seen the field through a QB's eyes."
I think it's terribly important - particularly with the young QB's we have (or may have) behind Blake - that we have someone who knows proper mechanics, can (through personal experience) work with QB's on "how they see the field", what to look for and how to react, how to sense a pass rush from the blindside etc. etc.
I'll concede that, on teams led by an offensive-minded HC or with an OC who was a former QB, these guys can fill the role of QB tutor. But in the absence of that, I really think having a legitimate QB coach is essential if we're ever going to get strong at QB.