Khan was caught with not one, but four punches to put him down, so I don't know where this Limmond can't hit stuff is coming from. He does not have alot of power, but 4 head hits will send almost anyoneto the canvas. Khan was walking about with his chin up and that's what cost him.
TBH I'm glad he hit the canvas as it will open his eyes to how tough his chosen proffession is and will hopefully make him a better fighter.