That analogy falls on its face because these guys aren't backups and shouldn't be treated like backups. Carr is a "starter" and DA is supposedly a "HC".
The problem a lot of Saints fans have is that they diefied Drew Brees and prmoted him mentally to a plane higher than human...so no one in their eyes would ever satisfy their expectation of a God QB.
For the CSP -> Allen that comparison is more based on logic and what they eyes actually see...we saw leadership/accountability/motivation/fear w/ xCSP -> we don't see any of that under DA....and the proof is in the W/L column.