I agree that said person should have prior experience before adding additional exercises, I’m not implying that it is out right dangerous from an experienced point of view, but to someone who has not practiced that self control, marathon runners vs sprinters, I can almost guarantee if said person jelqt for the first time, he wouldn’t stop in till a change has been observed in his penis, same for clamping and cock rings, once change has been observed the ideal man would want to keep it that way.
We can always assume we know too little of something when danger is involved, caution. An example: I’m going to learn how to swim today, and the response is?
The poster ask why?
I get good results with my home made velcro strap clamp/ring, I don’t use it all the time but it works, my apology if you misread my answer.