I think the lesson is don't blow off IRFS. If you're using a review course, it'll probably have the right balance between IFRS and GAAP, which is to say, mostly GAAP and some IFRS. I believe that in 2011, Roger (of the eponymous review course) said that the AICPA told him that IFRS would be around 10% of the exam, which is about how much government is supposed to be, right? So it's not huge, but you can't ignore it.
(If you got more than 10% consider that your memory is inflating the percentage because those questions were harder or that a bunch of those questions were not graded.)
There's no magic bullet for this; study for everything that is fair game for the test because you won't know what's on your particular test till you're taking it.
REG 82 (10/07/11)
BEC 88 (11/01/11)
FAR 86 (11/21/11)
AUD 82 (11/30/11)
----------
Roger CPA Review, live & cram course