W-L is a team stat. QBs really do not win or lose games all on their own. Do you think Dalton would be as successful in Cincinnati without that stout defensive front or AJ Green? How has Kaepernick looked against decent defenses this season?
Before Kaepernick was installed as the starting QB, the Niners almost got to the Superbowl with Alex Smith during the 2011 season. If not for some muffed punts, the Niners would have likely played in the Superbowl. Also, The Niner's W-L record with Alex Smith under Harbaugh was 19-5-1 . So are you going to tell me that Alex Smith should be someone the Bills should have moved heaven and earth for since he was such a "winning" QB?