[Harv72b]

Most of the time I'll 3bet this preflop, but I'll also sometimes just call the raise (especially against a passive or unknown opponent, but sometimes also against a very aggressive one). Against the very aggressive opponent, I will also often just call down unimproved, depending of course on the board.

I would have raised the flop, yes, because I would also have raised the flop with two hearts, a king, and against some players, a 7, pocket pair, or nothing at all. Most of the time in these situations you'll get more out of your opponent by going ahead and raising immediately, especially when the flop is drawy.

In this case I doubt it would have mattered, as his line indicates that he had absolutely nothing.