I've been surfing for decades and only recently perfected my Hang-10
I learnt that the rear of the board really has to dig into the curl of the wave for the balance to work. The only other way I managed a very quick H10 was to ride down a fast wall and quickly go to the front, but soon the nose will start to dig in. The only way to make the H10 last is to have a good amount of white-wash on the wave (rolling waves are best) and have the tail in there.
Your experiences?
Wingnut has some good tips too