So, you put Sanchez on the Bills and they are making 2 straight AFC championship games, and you put almost any other starting qb, and several back-up's on the Jets and they aren't making SB runs? Sanchez was bad before this year (55% completion rates, more turnovers than td's) aside from 6 playoff games (and if we are being serious, he more so didn't lose Cincy and SD than he actually won those games; he choked after Green got hurt in Indy, and was the difference against Pitt when he, shockingly, I know, fumbled for 6), he has just become even worse this year.
Based on what we've seen out of most of the other QB's in the NFL, no they wouldn't be making AFC Championship Game runs if they were here the last couple of years and Sanchez wasn't. Of the ten QB's or so who might have been good enough to win at least 2 playoff games on the road we know that most of them have not done that in their entire careers to date so I think it is silly to suggest that they'd magically have won games with the Jets that they cannot win on their current teams. In 2009 it would have taken 11 wins to get a home playoff game and both Indy and Cincy would likely still have been playing hard if they thought the Jet were a real risk to go all the way. That's about a 3 win swing and I don't think any QB short of the top 10 would have made that kind of difference in the Jet's season. So then you go back to would they have won on the road and the answer is no for most of them. In 2010 there's no way the Jets win 14 games particularly with Damien Woody getting hurt at the end of the season. The losses to the Ravens and the Packers were vintage Schotty's offense not being ready against a tough pressure defense. He's done this with every QB he's had at least a couple of times, including Kellen Clemens who lost exactly that kind of game against the Ravens after Chad went down.