Wait. You articulated exactly what likely the problem is with Chris Johnson this season, which is a multitude of factors: "...not having an offseason, a training camp or pre-season games...a bad team." I agree.
Yeah, it would be pretty hard for anyone to maintain a 1,500+ yard seasons, but did you honestly just glaze over the fact he did in fact have a 2,000 yard season, lol? For some reason that sounds strange to me like "yeah, Joe Blow is a good home run hitter, but that season he hit 90 really skewed the numbers."
I disagree about the too many carries issue. Emmitt Smith had way more carries through his first three seasons than Johnson. In fact, name me a great back (Tomlinson, etc.) and I'll show you a running back with a comparable amount, if not more carries than Johnson. Those two in fact had more carries than Johnson after three season than Johnson had going into his fourth (this year). Those backs have all had long productive careers. Perhaps Johnson won't be around until he's 34, but at 26 I hardly think he's "done" as some suppose.