I just saw this news story on Slashdot and it makes no logical sense to me. Let's say you have 33% of all mining at your pool. You have a 1 in 3 chance of finding a valid block solution before anyone else. So, you win it and do the exploit they say. You hold it and secretly work on a 2nd block since blocks are based on the data before them. Now you happen to find a 2nd block that works before anyone else does since you got a "head start" (only probability-wise, no progressively). Finding one valid solution is unlikely but finding two before anyone else finds one is exponentially harder. Then they expect them to find 3? It would happen less than 1% of the time.
Now the other problem is they claim "as soon as another pool is about to find a valid block, you release yours." That's impossible. As soon as another pool broadcasts that it found a solution, the others check it, and it's already too late. Work is non-progressive so you can't tell if another pool is "getting close." So then it'd be a gambling thing. If you find a solution and start working on a second one without telling anyone and claiming your 25 BTC reward, you're more likely to lose to another pool before you find a 2nd valid block value. So you'd be holding it, holding it, holding it, oops you lost it and got 0 BTC.