Right Hand Hammer-Ons, Tapping Question

This is a 6 minute video response from Nick Greathouse on Nov 1st, 2008

Question:

"bator82 asks, "Hey guys, thanks for the lessons. I was just wondering if any of the instructors knew how to do hammer ons with both hands. It seems like even when I know the notes, I have a hard time getting the sustain I want when I have to hammer on with my right hand. Does it have to do with the amp's gain, the guitar's natural sustain, pickup volume and tone, or do I need a compressor, or again, is it all in the technique. If so, are there exercises I can do to help out with right hand hammer ons and even slides? Thanks in advance.""