I like to say something about kegals exercises that I have noticed. Watch out for over training. I think its very common for most people to think that if a little is good, a lot more must be better. I recommend making a schedule and sticking to it. I used to do my kegals on the drive in to work and then when going home. Now I just stick to the drive into work. I do 4 sets of 100 and that is all I need. The last set I try to put some speed which really seems to put the stress to the muscle. I also get a dual benifit from doing my kegals when jelq’n.
Another thing I like to point out about kegals is that like all muscles, there are muscles for pushing and pulling. When I do my kegals I push and pull. When I added the push with the push in the kegal, I had an almost immediate impact on my erections. Much stronger for sure.
I have not had Pre ej but I will tell you what I know about extending the time during sex. When I feel an orgasim coming up, I stop immediately. Also, when I was young, I noticed when I masterbated a number of hours before having sex, I would last a long time too. My wife heard a sex therapy show and masterbating was recommended to the person asking about how to resolve Pre ej.
Hope something I have said will be of some help and correctly answered your question.
Manzwa