The key to the super bowl run for most of the "Run of the Mill" players is still that these guys had phenomenal season/post-season to put their team in that position to make the Super Bowl. Jake Delhomme, Rex Grossman and Rich Gannon (Of the top of my head) all had super seasons. Similar Flacco was super hot last year in the playoffs on the way to the SB win.
The bottom line is you still need a VERY GOOD QB On the given day. The question is is EJ consistent enough to put us over the top.