Fewell does neither ... hence why I don't think Jones would do well in our current defense.
It's my personal belief that the writing is on the wall for Tuck, and they try to replace him. They're already talking about swapping JPP and Tuck which doesn't make a lot of sense since Tuck isn't a speed rusher. The only speed rusher expected to be around in the first round is Damontre Moore who wouldn't be a bad choice, but I worry about his size (that and he doesn't have the freaky leverage of someone like an Elvis Dumerville). Moore is a little more intriguing since he's played both sides.
I think the Giants may find it easier to keep JPP on the weak side and replace Tuck with a Werner (if he drops) or Okafor. I'd love to see JPP slim down a little to get his step back (I think they overshot with him in that regard).