For sure Portis is good, but there are tons of good backs in the NFL. Put any of them on the Broncos and they'd be aweosme. Put most of them on the 49ers or another crappy team, they'd suck. I think actual RB talent has a LOT less to do with it than most poeple believe. It's almost always the system and surrounding players (O-line, defense, FB/TE, QB, etc) that makes players good.
Portis last year averaged 5.5 YPC. This year it's 3.9 YPC
He has half the TD's he did last year at the same point in the season, which Amazinz actually used as evidence that he's as good as last year
EDIT: When i say "good", I mean for stats purposes, not skill. Obviously the player doesn't actually get worse or better from team to team; his production gets worse or better.
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