If they start Sanchez, he should be benched after his 1st 3-and-out, fumble, or turnover with the game on the line. I think Mark has all the talent, but he is mentally not there. Turnovers (over and over and over again, with games on the line, no less!), bad press, fans turning on him, weapons keep getting hurt/leaving, team dropping his passes.... it all adds up.
If they start Tebow, it should be as a stituational option QB/RB, and not starter for the whole game.
If they start McElroy, then we'll find out a little more if this kid has what it takes to be a starting QB.
Don't overlook the Jags just because we trounced them last season. Remember when we killed Oakland a couple years ago and they got their revenge last year? This is the NFL... anything can happen on any given Sunday.