For many people, calming down the kick helps at any speed. If you've been racing a while, it's not so much that you try to do a two-beat kick, but that each and every kick fits into the rhythm. Even a six beat kick has one kick to snap the hips and two on each edge. On shorter races, the right kick will make the difference. Make sure it barely pushes beyond the streamline at full strength, but realize that the demand that puts on you can't be sustained for most people without extensive training even to a distance of 200 or 400. I can and have kicked like a madman in my sprints, but at the slightly backed-off tempo where I can still manage the connections between hip drive and rotation.