It's relevant because Peterson is the same guy he was back when Favre when playing with them and he didn't put up great numbers. So there is literally no evidence to suggest any correlation between bad quarterbacks hampering great RB's or vice versa.
Yet that didn't stop MOJO from being the rushing leader last year. Hasn't stopped AP from challenging the all-time yards record. Hasn't stopped many many others from having fantastic years.
AP wasn't seeing many 8 or 9 man boxes with Favre.....yet had probably the worst full year of his career.
It's one thing to lead the league in rushing, it's another to do it with over SIX YARDS PER CARRY. If he breaks the rushing record while maintaining his YPC than it'll be probably the greatest season of all time by a back. Do I think he wins the MVP? No. But does he deserve it? ABSOLUTELY. He's averaging more YPC than his quarterback is YPA.