Flopped Monster Boat

[Walter]

If he is overaggressive, then why not check and give him a chance to make a move and tie himself to the pot if he does not put you all in?

What would he call you with on the turn that he will not bet after you check? You were representing a made straight with your check on the flop then checkraise on the turn. So he can only call with something like A7s or Ac9c or something better.

If he doesn't fill and you move in, he won't call, but if you check he might try to push you off your hand by representing 78, a hand with which he might have used a small pre-flop raise to build a pot.