You have to carefully choose a DT. Out of all the DTs we recruited last cycle the leading tackler is Ben Bradley with 13 tackles. And if you add Russell, Johnson, Peko, Bradley, and Hooks together they've only started 6 games between of all of them. I do remember hearing one of the recruiting analysts say that Clinkscales is the best JUCO DT they've seen in 3 years.
I believe you're referencing McKewon... See post #106.
One thing you've got to remember with DT's is that with some guys, specifically nose tackle types, unless they're very good at block shedding, agile, or otherwise just freaks of nature, sometimes their stat sheets may remain relatively barren. Some of these guys may be your proverbial "space occcupiers" that just serve to soak up a couple blockers and free up ends or backers. I don't recall, but I would think a few of those guys fit that mold.
I think a better metric would be taking a look at some trends for teams that recruit these guys (for the ones that end up making an impact, anyway) and looking at certain things like team run defense, TFL, etc. Obviously, there's a lot of variables there, but if you correlate that with individual statistics, you can find out who was actually a good get and who wasn't.