I too have had improvement in erectile function from PE. Harder erection and night-time and morning wood. I also rarely loose my erection after I orgasm.
Back to the point of the thread, I have read that once aging starts, elastic fibers are not repaired. Similar to how the elastic fibers in skin are not repaired, i.e. wrinkles, stretch marks. I agree that the individial cells get replaced but the way I understand it the fibers do not mend once they are stretched or broken.
When I have the time and inclination I will look again for this information and post it. I think I was doing a search with the string “dense connective tissue”.
Please don’t think that I am trying to put a scare into anyone. Only a few people on this forum research the science behind why PE works. I am one of them. If there are side effects to doing PE, I think it is important to get that information out also.