Starr did a nice job in that five year window you mentioned, but he had below 60% completion in three of those years despite never having more than 285 attempts in a season. He was a solid QB, but I compare him to Tom Brady in that he benefitted from playing for the right team and in the right system.
Heck, I think that Fox should have been fired the year before after the Raven game. Here's why: When he was hired four years ago, the expectations weren't nearly as high. He was the right man to change around a locker room that got poisonous under McFail.John tends to be decisive. I actually thought he would fire Fox after the Super Bowl debacle. He probably wishes he had, now.
However, the next year, the expectations went way up with 18 coming to town. Fox wasn't the guy to meet them. It's too bad that John didn't realize that then.