I tried palms up jelqing - fast (like in that video) and slow. Fast and light achieved little for me while slow with a tighter grip brought pain in a vein near the base of my penis. I now do a palms down grip with 3 second strokes with a moderate grip and I get a great all around swell and no pain. The palms down allows me to get much more into the base when begining the stroke which I think is very important - much more blood to stretch your whole penis. No matter how hard I try, I can’t get as close to the base palms up than I can with palms down. Plus, the palms up was hurting that vein (my guess is because blood was getting sent in the opposite direction stressing it - going more in the base lets me get the whole vein into it).
That’s just my expereince anyway.