Last year per the coaches, it was incredibly important to have a quality backup (able to step in and win), not a mentor.
I guess that changed this year... It's now more important to have a mentor... I guess getting mentored for one year by Brady and 2 years by Luck didn't help?
QBs come in all the time and start day one. JB has been in the league 3+ years now having great mentors his first 3 years.