Most review book companies would disagree with you, but I see where you're coming from.
That being said, it depends on where you're starting. Personally, I had zero difficulty transitioning into passage based questions. For some people, it's the main game. But my background is as someone who has always been exceptionally good at standardized testing/critical thinking exams, but had taken most prereqs 5+yrs prior when I was a crummy student. So for me, content review was key because the test-taking component was never a concern.
I think in sum I would say: you need a certain level of both, but the content review threshold is probably lower than most people expect it to be coming in. What you should focus on depends on your own strengths, and if you are severely deficient in one, you can make it up partially focusing on the other (for example, someone who is a very slow critical thinker/test taker can study multiple approaches to each concept, greatly speeding the process when the test tries to throw an atypical presentation at them).