How could you ensure it? The button, small blind, and big blind could wake up to QQ, KK, AA, or AK. Each of them has almost a 2% chance of being dealt one of those hands.

I think the play is a very close one. I would guess that it might be +ev from the button if certain conditions are met but from the co, I'm guessing it's -ev. JTs plays well against AK, AQ, KQ and medium pocket pairs. You are in big trouble if you're up against AA, KK, QQ, JJ, TT, AJ, KJ, KT, QJ or QT. The question is whether your position and the additional blind money can compensate for all those hands where you are dominated. You have to to take into account that the button/sb/bb could call or raise no matter how unlikely you may think it is. Your opponent's level of post-flop play is going to play a role as well.

This is a play I'd much prefer to make against a very aggressive player or a tilting player w/ a tight button and blinds behind me.