I've made Nancy Silverton's croissant recipe (available on epicurious.com) many times without any problems. I'll admit that it's been a couple of years, but I really befuddled this time around. The only ingredient that was different is that instead of Plugra butter (not available at WF yesterday), I used Straus European butter. I think that butterfat % is higher than Plugra, and that may be the issue, but what's happening is that there were a lot of discreet pieces of butter visible through the dough (even at the end). When I was forming the croissants, they looked pretty raggedy. Then, they didn't rise as much during the final proofing. They're in the oven now, and of course the butter pieces are melting all over the parchment.
Does anyone have experience with this butter? Was this the wrong choice? Could I have inadvertently done something else different that is causing this problem?