Rex had the ancient Brunell as a backup the last two seasons
Now he has McElroy who will likely be nothing more than a 3rd string QB due to his arm and Tebow is basically Sanchez with legs as he is clueless when it comes to reading a defense, has horrid accuracy, and makes stupid decisions with the football.
Also Tannebaum has stuck Sanchez on next year's team so Rex has to account for him being next year.
It's so important to have a good QB in the NFL and Tannenbaum has saddled Rex with possibly the worst starting QB in the entire NFL with no legitimate backup options
For all of the teams flaws, with just slightly above average QB play the Jets would probably not only have won yesterday, but possibly the Texan and Patriot games as well.
Unless the team completely implodes down the stretch Rex's job should be safe.
Tannebaum's is a different story