Sure, this has been brought up, but what in the world is going on here? 7 carries for the season 4 of which were against the Texans (not much happened there). Greene is ranked 30th in the league (DVOA), yet the Jet offensive line is ranked 4th in power rank - Power Success: Percentage of runs on third or fourth down, two yards or less to go, that achieved a first down or touchdown. - and 6th in "stuffed". The Greene-fueled OL is ranked last (32nd) in both 2nd level yards and Open field yards, just as these longer run rankings were poor last year with Greene as the primary back (near dead last). So the OL isn't getting stuffed, it is able to convert short power yards, but it is dead last in anything beyond 5 yards.
It could be that some of this is teams still creeping up to stop the Sanchez short pass, but in all likelihood it really has to do with Greene. You can tell that they are trying to make something of a move to Powell, but he can't seem to catch a short pass (targeted 7 times the last two games, zero completions) a pass which for some reason OCs think is a major part of Sanchez's arsenal. Is McKnight just OFF the field because he can't help max protect Sanchez, I seem to recall he has okay hands coming out of the backfield? - if so, Sanchez is having an effect on the running game too). Can he really be worse than Greene though? Is the offense really so complicated? Is there something personal with the Offensive coaching staff - Rex did joke the McKnight had been "traded to the Defense".
In any case for a team downright starved for creative, dynamic athletes on offense two of the most dynamic players left on the Jet roster on O have averaged very few touches. McKnight has averaged only 1.4 touches and Tebow 3.5 a game, those are just touching the football.
As for the McKnight to the defense, he has had 2 snaps on D.