There's another point here that's worth bringing up, I think, bearing on the question of fighting range that LF included in his original post.
If you think about the geometry of a low-to-mid kick vs. a head kick by the same fighter, it's immediately obvious that your distance from your opponent is going to have to decrease as the height of your kick increases. If you stand at the same distance where your turning kick lets your instep or the ball of your foot make impact with your oppo's waist at full extension, you clearly won't make contact with if you instead aim the kick at his upper rib cage. So you have to move a bit closer to strike that target. But now, at that distance, assuming you're at full extension on the kick to side of his ribcage, you'll miss his chin cleanly if you increase the angle of your leg to kick to reach that height. So you'll have to move in further still to make contact to that target. And so on. There's no way around it: if the long side of a right triangle (your leg) is fixed in length, then the only way it can reach a given height as the angle of your leg to the floor increases is for your horizontal distance from the target to decrease. That means that a head shot with a roundhouse is going to put you in very close quarters anyway. This means that if you want to max out the distance between you and the oppo, you don't want to kick high; you want your kick to come in parallel to the floor—it's at that height that you get full contact with the attacker's body at the maximum distance from him.
So a head shot commits you to a CQ fighting strategy anyway. And you have to ask: given that you're at H2H range in any case, which gives you a better advantage in terms of balance, speed, and the chance to switch to alternative tactics if your first tech goes sideways: a high-kicking strategy, or a strategy involving aggressive hand techs with kicks reserved for the finish?
