I'd say it's pretty safe to say he's never doing this with hands you are beating preflop. On the off chance he does this with broadways then you're still totally screwed on the flop since the most likely broadways he would have in this spot are all now 2pair and thus causing your bet to be spewy. It's hard to get away from min 3bs preflop but if you do call I'd be trying to get to SD as cheaply as possible unless you flop the nuts.