Tom,
The comprehension comes in layers with repeated exposure to the material. You don't memorize the material unless you want to and work with the material for that goal. Memorization is easier with the PRing techniques, but it does require some effort.
Just like many others who PR, I had unrealistic expectations when I started PRing and erroneously thought I would be able to have immediate recall of all info that I PR. Having said that, after doing the 5 Day Plan (outlined in other posts), I now understand how the system is supposed to work.
Purchase either the book or the course, start learning the system, and do the 5 Day Plan. If you don't like the results you have two options. 1.) seek help through LSC or this forum, or 2.) return the material to LSC within 30 days and take advantage of thier money back gurantee.
Above all play with the system and have fun.