I'm not too worried about the juror staying in the SA is trying so hard to strike. I also didn't get the impression she was all that intellectually challenged. I haven't been able to follow every minute of this, so am not on top of which juror is which, but I saw quite a few come on and be asked basic questions they had difficulty answering.
IMO, these PJs are just average people. They have been called in from their regular lives, been made to wait around for hours and/or days, finally get called into a courtroom with cameras, even if they aren't having their faces put out there, they are being recorded and put on TV. They are taking the stand and being questioned by a judge. They are being questioned by numerous attorneys. Some of these questions are personal. And all of this done in the presence of an alleged child murderer. I don't think we are seeing most of these people 'at their best'. IMO, it's going to be a rare person who is completely at ease in this kind of situation. I would be a nervous wreck.