It has been said throughout the media as well and not just on here is that you run a limited playbook with TT, for a rook who will be on the bench and learning I would prefer not to have to run and practice with a limited playbook...
Also I would rather have a QB who can make reads to be able to help groom the rook - Fitz, McCown are those guys, TT isn't
As a person I love TT, he is a class act and a backup. He is also not the right person to help a rookie imo