Not sure I agree about Wilfork and Jenkins. NT's and DT's anchor the line, and being heavy, real heavy, is often an asset. Ted Washington was huge, but he could move. So can Wilfork. I don't know about Jenkins, but I assume he can or he'd be ineffective.
Woody (and OLine in general) is different. They NEED a certain amount of agility. As a Patriot, Woody was very good, but he often let his weight get too high.
I have no idea why coaches like Weiss and Ryan get surgery. I mean, it's because they are way too fat, but do they have so little discipline they cannot shut their piehole for a couple hours a day? They don't need high weight to block or attack blockers, so just friggin eat less. It ain't rocket science. We're not talking about an extra 30-40 pounds. We're talking 100+ pounds too much. You have to eat a LOT to maintain that bulk.