Not convinced doing 10x10 is the way forwards in OLifting...
How is 10x10 derived?
The 6reps x 6set means this = 1 CJ = 3 reps of squats,
1st pull and 2nd pull = 1 squat
squat up = 1 squat
jerk = 1 squat
=3 squats (this is also where you get the quoted figure of you should be able to CJ about your 3RM from)
CJ for beginners I get to do doubles = 6reps
I have them do about 6sets of doubles for CJ or 6sets of triples for Sn to begin with. This is where I get the 6reps x 6sets from.
The % is irrelevant. It's a basic guide to use a weight that is not too light. The overall goal is that this will go up. After 6months or so we will go heavier more often but for a beginner it's better to build a base. Again depends on the lifters background.