https://www.youtube.com/watch?v=yBmvSmIrToo&ab_channel=FightHype.com
Ok STEP 1
Keep the hip ON activated AT IMPACT and even AFTER impact you turn it on at the start of the punch and it goes OFF at IMPACT with the target probably because you are focused on what your arm is doing (the long hook motion) rather than what your hip is doing
STEP 2
Get close to the heavy bag and throw small range of motion left hooks with a 90 degree angle, until you find that easy, keep the hip on at impact remember, do TONS of reps. Once you can do that with EASE move onto medium range of motion left hooks until thats perfected.
STEP 3
DROP EVERYTHING ROY JONES JR he doesn't want you to be the heavyweight RJJ because then he looks bad by comparison, hint hint (hes got you slapping) Technically the way he taught others how to do it it is ok, but also incomplete, he leaves out vital information, ALSO its the most complex bstard way to learn it, and thats how hes showing everyone.