Keep palm pressure before releasing the fingers
After levering the club back, continue pushing the palms forward to retain the lever before allowing it to release. Starting the release by flicking the index fingers makes the palms and handle move backward while the clubhead accelerates. The described sequence is to lever the club back, lag the lever with continued palm pressure, and then let the fingers work down and around the palms.
Channel: stayhandsy
Watch official source at 26:47