"given the nature of the position and that alexander isnt alone in the drop off id say its very possible."
But LeSean McCoy and Shawn Alexander weren't very similar RBs in terms of playstyle. LeSean's playstyle is very similar to that of Barry Sanders', and he kept that up for 10 years. I'm not expecting him to do as well as Barry, but I'm not expecting a dropoff.
"all im saying is you have to be careful with a deal like this,"
Agreed, but you have to be careful about every mega million dollar deal.
"as you proved when you werent even trying to"
I said "Well, Shaun Alexander kept it up for exactly five years, and you saw how fast he fell off.", in a sarcastic manner. It was meant to portray that someone kept it up for a couple of years before falling off, so there was at least a "set" # of good years to expect. There is no way I'd expect a RB with LeSean's playstyle to fall off as fast Alexander.