Interesting Way to Play a Flopped Set

I was watching Poker Royale: Masters vs. Young Bloods the other day and I found a play made by Michael Gracz to be very interesting. Gracz had pocket 4's and called a raise by another player that was about 3 times the BB. Gracz found a 3rd 4 on the flop, but when it was checked to him he also checked, and again on the turn it went check-check. The turn also paired the board giving Gracz a boat. The opponent actually held A-J and when it was checked to Gracz again after a river 6, he went all in. I believe the board was something like 10-5-4-10-6 with no flush possibilities. The player with AJ thought it was so suspicious he actually called with ace high and doubled up Gracz. (critique that play however you wish). I was just wondering what everyone thought of that play. I no it can only be used under certain rare conditions, but I thought it was a unique way to mix up your play and was a way to try and get money out of your opponent when he won't put it in any other way other than an off the wall play like that. I know many of you ask why the opponent didnt make the standard continuation bet, but like I said this can only happen under rare circumstances.

It would have been the texture of the flop that dictated Graz's play, i.e. board of 10-5-4 if his opponent checks he likely hasnt caught the board (you'd bet a ten to protect against overcards), then the 10 on the turn by the same reasoning; Graz was hoping that his opponent would catch up so checked again (even better if flush draw on board). The 6 on the river is unlikely to fill a straight as 3 x BB pre-flop raise. The overbet on the river is quite canny though, maybe an opponent is more likely to call an overbet than a value bet? I've not tried this but interesting, I may give it some thought.

[soko]

How big were the stacks?
How big were the blinds?
How big of an "all in" bet was it?

The pot is only 6 big blinds, but that might be half of one of their stacks late in a tournament when the blinds are about to gobble him up.

Not much I can tell from this post from the the information given.

villan needs an incredibly strong read to make this A high call. And it seems a little suspicious the way the 4's played it. More times then not this is just going to horribly de-value your hand by not betting anything.