It's fair to look at, but for anyone that has watched these games you've got to admit that Tannehill has far more ability and promise than Henne. No two situations are ever going to be the same, and reasons can made to support either side. Henne also had some pretty serious hand cuffs put on him.
Tannehill handles pressure better, is far more accurate, has touch on his passes, is more mobile, and commands the team better.
They both had 4 wins in their first nine games. And they both had some heartbreakers. That was the year that we should have beat the Colts and the Saints.