Well there is some faulty logic there.
Failbin signs his own pink slip by CONTINUING with Tannehill. Its OBVIOUS at this point that the team will not generate enough offense to win more than 8 games with Tannehill. If that happens, Failbin is gone. He has to know that. So moving forward with Tannehill is a guarantee that Philbin is gone.
Benching Tannehill does not guarantee Philbin is fired. What if Moore comes in and gets us to double digit wins? If he starts Moore beginning NOW, he still has a shot to keep his job. If he continues with Tannehill, his job is gone.
In fact, if I were Hickey and Ross, I would fire Failbin TODAY if Failbin told me he wanted to start Tannehill this week.