i mean if it's done with focus and intensity u can still get some gains from it. if u just do it quick and sloppy to get it done with probably won't be gains. but if u work on perfecting the technique, get intuitive with it, and use some arm strength and get good at increasing and holding an expansion then it's a different story
but if u add more exercises or follow some program u would target more areas and dimensional planes for growth in more than one area
just jelqing can bring some gains but it will create a certain look which will be some length and probably some upper shaft and glans expansion
that could be enough, it all depends on your goals and what u want or can do
it might be good to just start with jelq, perfect it, and then in due time add another exercise to the mix
for instance whether i'm doing PE or working out at the gym i like to incorporate a new exercise every few weeks at least whether it's just 1 exercise or a few
but i've also seen some guys make solid gains from a simple routine. like there is a guy on here who literally just did manual stretching throughout the day any time that he could and he gained like about 2 inches in length in about a year or two i think? pretty awesome
