Latest LSAT nightmare: I felt great walking out of the testing center....then to my horror, I realized I didn't put my name on my answer sheet. *has heart attack and dies*
I would say at least one pt per week but no more than 3 or 4 pt per week because you need to make sure you have good quality of time to blind review every question that gives you trouble during the PT and avoid burn-out.
I usually read it once to locate the premise and conclusion to avoid mapping out the irrelevant parts that they throw in sometimes. Honestly it always would take me a long time :)