I am not sure that I understand what you are trying ti say. You are saying that because you have good OD, you started training JS and you got a pop-up in JR after 7 and 9 weeks for each player!! So you believe that someone can pop with 2 weeks of single position training in JR. Am I correct?
So what is your explanation in my case? I have OD 11 and JR 9. Why didn't I pop after 3 weeks single pos JR training?