Jerry, here's a better video on balling dough
The tricks with balling, and I think Chau does an excellent job of showing these, is that you want to
1. keep the dough ball round as you fold it into itself
2. fold it enough times so that the outer skin gets taught, but no more
3. pinch it shut gently
It depends on the hydration of the dough, but for traditional NY style levels of hydration (60-65%), if you go overboard with the number of folds or pinch the dough aggressively, the exterior will tear- and tearing, at this point, is not good. Here's a video of how NOT to ball:
If you haven't really gone to that great lengths to ball the dough in such a way that you get a nice taught (but not torn) exterior, then I wouldn't bump up the knead. Unless you're kneading very slowly and methodically, 5 minutes is plenty. My flour has more protein than yours, so I get gluten development very quickly, but I mix for 1 minute to achieve a 'shaggy mass' stage and then knead aggressively for 2.