That's a bad contract for a receiving only RB and completely unlike the Pats model of value.
11 M per year in RBs? What the?
Yes, although NE can usually plug in any ole rookie RB, there is a 1yr or 2yr growth period, and more than a few flame outs with FA's or rooks. BB is loading up on "sure" things, or as much as you can get in the NFL.
I think as to why, we are seeing are two contributing factors:
1) NE has the cash. Fiscal responsibility and increasing cap projections, have them looking pretty good.
2) BB wants to keep this team from experiencing the slight dips and zags of growing pains / acclimation periods , IMO signifying he's loading up (more than usual for NE) for the twilight (2, 3?, 4??, 5??? yrs remaining) of TB's career. Reading between the lines, if you look at all the moves as a whole this off season, unlike past seasons where there was a balance between immediate yrs 1-2 and not so immediate yrs 3-4+, these moves are a bit more front loaded. Heavier expected returns on yrs 1 & 2, ok on yr 3, and a bit less concerned with years 4 and beyond. This is not this deal only, this is all the deals so far this off season; trading away early and mid picks for young established players with less years of control, slightly overpaying for RB positions, keeping established core players instead of the usually roster churn, are all examples of a slight shift in BB's team building (GM) priorities a bit. All logic trickling down from maximizing TB's (remaining) value a bit differently than you would have 15, 10 or 5 yrs ago. IMO.
Edit: The logical extension of this, is that we're sure to see quite a few OL in the draft, more so than other positions. This is a good type of pick that plays into a 2-3 yr window with current roster/contract setup, I.E. Keeping TB on his feet. Not only that, but there are sure to be a few rough diamonds OL at the spots we are picking. Which as a whole wouldn't surprise me is the entire draft strategy for all positional picks, going for high risk, high return guys that can pay off big in a short window, or cast off from a deep deep team if they cannot.