I'd only 3b preflop if I was sure to be called by worse or I would fold out better. And I don't think better is folding.... If you believe you'll most frequently be called by worse, great. Then on the flop I check-fold. Because the worse hands we believed were calling us preflop are salivating over this flop and the fact that they have position over us and the fact that we narrowed our range by 3-betting. And if villain checks back the flop, it says A LOT more about their hand than if they call a cbet.