Lightning Quick Carbonation

[wqijno]

I bottled my Belgian Wit on Wednesday night, I always bottle a couple in the plastic Coopers PET bottles to squeeze them to test when they're ready. Well it's only Saturday and the PET bottles (which have been sitting at a coolish room temperature) are already very firm to squeeze, can't see any sugar swirling around, and the yeast is settled nicely at the bottom. I was thinking maybe the aggressive nature of the safbrew S-33 yeast might be the answer since the fermentation took off like a rocket and was very violent for the first couple of days. And I don't bulk prime so each bottle had a precise amount of sugar. Has anybody else had their bottles carbonate in less than 3 days?