How did I prepare for law school?
I did not prepare coming into law school other than a "how to succeed in law school" book that my school suggested (which wasn't really much of a help). It never crossed my mind to prepare by pre-learning some of the material because I had never done such a thing for any school work in the past. But I realized pretty quickly that law school is different than any other past experiences. Knowing that now and based on my experiences with law school thus far, I think prepping would have improved my grades for the first year.

What makes me think that prepping before law school would have helped?
I was lost and learned almost nothing throughout the first semester in class. I couldn't see how cases fit into the big picture and didn't understand many rules. It wasn't until I sat down at the end of the semester and started making my outline and going back through other resources that were more focused on rules/black letter law than casebooks (ie, past student outlines, CALI lessons, commercial outlines and supplements) that I started to catch on.

What if I had just gone over those types of resources before classes started? I think it would have saved me the stress of being lost and the time of trying to learn everything, including the easy stuff, at the end of the semester.

Who should prepare for law school?
This sort of self prep is in no way for everyone and not a lot of students do it. It takes a lot of motivation to put extra work into the summer before law school and continue working hard into law school. And burnout is definitely a concern.

To me, ideal candidates are students who feel like they have to achieve high honors in law school, say law review or a top associate position.

Students who would like to transfer to a more highly regarded school seem to be perfect candidates for prepping. If you want to transfer upward, you only have one year to prove your worth, and often competition at these schools are fierce because you're not the only one who wants to transfer. So if you're highly motivated and in this position, it might be something worth looking into. Some students from the Planet Law School message board have been in the same boat and a lot of testimonials pop up thanking Planet Law School for their grades allowing them to transfer.

Granted, there are likely to be more testimonials like this than ones by people who have prepped and not succeeded. Plus there is no way to know whether a person who prepared for law school in this way and excelled would have done so anyway. But looking back at my experiences in law school I can definitely see how the basic familiarity that would be gained through this method of preparation could help so it makes sense.