[Masquerade]

I think there's a very small chance villain is bluffing. In fact I'd put him on a big pair JJ-AA. He's going to like this flop but perhaps not put you on diamonds until its too late.

I don't think there's much point betting big here as any good player is going to raise you (unless he has JJ when he might call) sufficiently that you dont have odds to call. Checking and calling is rather lame so that leaves the weak bet trying to get a cheap turn. If this works and the turn is a diamond you'll need strong nerves as he may well raise back hard if he has JJ or AA with the Ad.