You know after Tennesse signed Ryan and a few other's I thought they were done, at least as far as big money deals go, but after your post, I started looking into their FA signings, and it seems like they still have a TON of cap space. So yes, now I'm more worried. (Thanks for that BTW- You couldn't just leave me with my delusions)
In fact it looks like they are making a big, but reasonable push to get him. Robinson, a Pats alum, isn't going to overpay any more than Bill would, so if that's the case, its really going to come down to the pull of his home town vs the pull of he old team.
So it probably isn't going to be about the money as I imaging whatever reasonable deal Tenn offers, the Pats will match. This will likely be a life style decision. I guess he has a girlfriend he lives with, but no kids, so he can up and move anywhere in an instant