I don’t even remember if I’ve given my take on this, oh well here it is.
I don’t believe there is a hard and fast rule on this. Masturbation and sex can be stressful to the penis. The variables are how stressful is the masturbation and sex is and how much stress can you absorb with no decrease in EQ.
I think the deciding factors are the effect it has on your EQ, and what type of PE you are doing.
If you are doing smooth muscle INDEPENDENT PE such as hanging, then I think it has very little effect, but of course the bottom line will always be if you find your rate of gains slow. In general, I think it will be less consequential with this type of PE.
If your PE is smooth muscle DEPENDENT, such as jelquing, clamping, pumping, etc., then it will have a GREATER ability to effect it.
You will have to see whether after you apply stress (masturbation or sex) you have decreased EQ ( shrinkage, decreased nite and morning wood, harder to achieve erections, less hardness to your erections) and how long it lasts.
So, if after sex, you find flaccid is fine, nite wood is fine, no real change of EQ, then I think it is fair to say it will have little to no detrimental effect on your PE. Go for it!
However, if after you apply stress, you have contraction that lasts for more than 30 minutes and see a noticeable decrease in EQ that lasts for hours or more, then it is very likely that it will impact your PE gains negatively.
Personally, I find edging can have all the stress of PE, with none of the gain potential. Of course, a short course of a few minutes is far different than hours…you have to judge the impact it has on your EQ.
The reason this has been controversial is that some guys report they can slam their dicks in a door, fuck for days and days and still get gains. Others have reported that gains come to a halt if they jerk off afterward. Both reports are correct, because there is a huge variation in both the stress and ability to handle that stress among guys.
So the short answer is (for those still awake after trying to follow this) is you must assess your individual response to the applied stress.