The basics of TRHbj (named by LLCoolDave) resembles 3BJ a whole lot. It's a bit faster and you gain more height on the unmorph.
To perform the TRHbj you have to start off as the hbj in Prime 1:
Lay a bomb. Then lay a bomb before the first one goes off, so that when you return from the first one the second one goes off before you hit the ground. The fourth bomb comes at the peak from the first bomb, and the third bomb comes a bit before the fourth. After the second bomb you should reach the peak, descend to the third bomb which then goes off along with the fourth bomb. The best time to unmorph is a bit after the last bomb, for the best referance, look at the second video.
The bomb pattern creates a rythm best explained as "press, press. press-press"