And as I was saying...
Review books....
It is very, very easy for the USMLE writers to "beat the review books", and they do
exactly that. The writers open up the review books, and check out the mnemonics. Then they find the one or two things in the same list that
didnt fit into the nice mnemonic, and ask you about them. They look at the page with different forms of the same graph - frank starling, tidal volume, volume/concentration-square things - for you to memorize and recognize on the test. Then they ask you about the variant of the graph which doesn't appear in the review book. They make sure to find out if you know the concept, and havent crammed.
They also have a lot of other tricks up their sleeve. They ask the same question 5 different ways, group some topics and scatter others, just to see if you know concepts, or have crammed trivia. The USMLE website even says that they can "statistically analyze" your test for irregular behavior.
I wouldn't be surprised if you lose additional points for inconsistent answers, suggesting random guessing.
C'mon man.

Dont you think the USMLE writers, the gatekeepers of the medical profession, are smarter than that? They want people who can think for themselves to do well on the test, not the ones who can memorize First Aid.