When I H/T I let go of the clutch at the end of the throttle stroke (read: at about a moment after I just blipped the throttle) I blip the throttle to the ideal RPM and then let go of the clutch at that point. It takes patience and practice to be able to tell what RPM you need to be at a particular speed. It took me a long time to get used to twisting my ankle enough to get my heel to blip the throttle. Then I broke my right ankle and had to re-learn the whole process again minus some flexibility. Just practice, but I think smoothness is the key, not necessarily how quick you let go of the clutch.

 

Yup! Instant throttle response + light flywheel + short throw for shifter + gas pedal pivoting on the top = fun to heel-toe!