Short is not a NT. at least not in the traditional sense. can't imagine a team drafting him to play there.
He's a pure three tech. He's quick off the snap and does a good job of making himself skinny, but has a tendency to turn his body too much trying to get through the line, and often ends up with his back to the play. But as a penetrating DT, he's up there with Richardson.
Unlike Richardson, he isn't relentless on the field. But that's almost unfair, because 8've never never a DT play the who.e field like Richardson does.