I used to think this as well but the facts don't indicate this....
Brady has never lost to Atlanta, Chicago, Dallas, Jacksonville, Minnesota and Tampa Bay, combined 26-0 vs. those 6 teams.
Vs. the AFC East: 66-20 (.767)
Vs. the AFC North: 25-7 (.781)
Vs. the AFC South: 33-6 (.846)
Vs. the AFC West: 22-14 (.611)
Vs. the NFC East: 14-5 (.737)
Vs. the NFC North: 14-3 (.824)
Vs. the NFC South: 13-3 (.813)
Vs. the NFC West: 7-4 (.636)