Tebow isn't beating the Broncos with his arm--he's thrown only
one interception (you could say
no one can catch his errant throws, but that would be uncharitable). So his legs are a huge offset to his poor passing yardage--and last game he even passed better. It may even be that his running ability is starting to help his passing, if defensive backs are starting to look for TT's scrambles rather than covering their men.
Add to that the team's appreciation for him as a leader and their realization that to succeed he needs their help, especially the defense's, and you've got 5-and-1.
So his legs are a huge offset to his poor passing yardage I watched his last game and Tebow's first several throws were flat dropped by the receivers. It may be his south paw spin on his passes are hard to handle, shades of the young Kenny "the Snake" Stabler. His receivers will catch on with practice or the Cowboys can get receivers that can catch a lefty.