Doubt that villain is just shoving with his eyes shut and his fingers crossed. He is repping a credible hand because he can have Adx Kdx a lot, not to mention that he was repping strength on the turn so could have a lot of Axdd and Kxdd hands.
I know you're well into your reads on other players, but in this instance it seems possible that he may have got a read from you?
As Alex said, all our strong draws and hands should be shoving the turn, we didn't shove the turn, therefore he doesn't think we have a flush of any description.
How was your posture when you called the turn? Did you look like raising or did you just call quickly and confidently? Did you tank?
Having played the hand back in my mind, I was forward with my posture throughout, leaning on the table, because I wanted to get as decent a view as I could (without being too obvious) of my opponent.
I paused before calling pre - was mulling all options (and chose the worst) - but called the flop relatively quickly. I thought again on the turn, which was again to consider the options and, again, to choose the worst of the three.
Calling on the river might well have given him what he wanted. He wasn't looking at me much, albeit with the odd peripheral glance. If he were, I'd consider it unlikely that's where he sensed weakness. Much more likely it was in the time taken to call and the fact I didn't raise.
I'm slightly surprised he didn't think I could have a big diamond, given the action, but I think he came to the conclusion he was barelling, so long as I didn't show any aggression.
As for his bet sizing, I think, looking back, he was concentrating on his bet sizes on relation to his stack, rather than to the pot. I think I would have taken a more SPR-centric line with my bluff and found a way to jam the turn.
I see a lot of people these days on the TV betting smaller with their c-bets than their 3bets. I was aware that he bet more, here. Is there anything to be garnered from that? What do good players think when someone does that on this kind of board?