I randomly guessed on the hardest passage and returned to it at the end with the remaining time I had left. I learned this technique through a prep course.
Okay so it goes without saying that each student is unique and if you can find an approach that works for you, then you should just stick with it and do your best.
Now, having said that.
I think this idea of skipping around is
terrible advice. The new MCAT presents the questions one at a time, so clicking through a passage will take longer. And, as we say in May, you may very well experience lag between clicks. Meaning trying skip back and forth is, at best, a minor waste of time, and at worst, a way to kill your rhythm and timing.
On the new test, including the CARS section, simply start at question 1 and make your way to question 53, in order. Use the "MARK" function if you're really stuck on a particular question.
As noted above, they've upped the time to 10 min/passage (and upped it from 1.5min/question up to ~1.7min/question). An extra 1.5 min may not sound like a lot, but spread out over the whole test, that's an ocean of time. On the old MCAT, I can't tell you how many students I had who "just needed five more minutes".
But now that everyone has 10 minutes per passage, it's going to be extremely common for students (nearly all of them) to finish in time. With time pressure off, students will be able to give an extra moment's thought to questions and the % correct will likely drift upwards - meaning it'll be harder to beat the curve.
So skipping an entire passage (which was always a bad idea for most test-takers) will now become even worse of an idea.