Yes and no. There are certainly great back out there who defy that dime a dozen mentalitiy. But, and a huge but, I don't know if a McCoy-esque player would be worth the contract on a team like NE. When so much of your cap is dedicated to a QB, I don't think it's necessarily smart football to also dedicate big money to an RB. Especially in their system.
Obviously, I think McCoy is and has been a special type of RB. I have him a little lower than AP, because to me, AP takes over games moreso than Shady. I think there's the "game-manager" approach, where you rely on a very special back because your QB can't do it all on his own, a la Teddy and AP, Smith and Charles (in the past, not so much these last years) and even TT/Shady. But if you have a $20M year cap hit for the QB, something has to give on the offense and RB is probably at the top of the list. Especially because that position gets hit with the injury bug so frequently. Having a stable of cheap rotational guys fits their team building strategy a lot more.
Just MO, of course.