Nope, I agree that injuries played a role. But it's also true that there have been a number of teams during this same period who have over comes similar circumstances and still managed to win with back-ups. And yes, as the years go by, the injuries and circumstances (coaching selection-player decisions) including Bradford or even Hill take on less meaning from the perspective that there are and will always be obstacles and injuries.
But it's what the team and coaches do to over come or at least minimize these circumstances, injuries and deficiencies that matters most. How long have we discussed the needs for a competent back up at OB? Or the critical needs of the OL? How many years has Fisher mentioned the excessive penalties week after week and month after month (they managed 12 today) or the bone headed acts at critical moments? Yeah, for awhile it's "we gotta work on this or that", then it becomes the injuries, or whatever the latest whiz bang explanation happens to be. Meanwhile during this same period, every other team in this division has won the division title (or more) and in far less time and in some ways with less talent.
So yes Coach, the injuries and so on eventually become tired and begin to represent little more than excuses for continued failure.....I guess that's easier than taking responsibility for real change. Certainly there are legitimate reasons for a lack of success during some period of time, especially early, but after past 4 years, there appears to be a pattern here of sorts.