In response to previous comments about two point, sorry couldn't be bothered doing the quote thing:
When you start off riding at the track you start with a slightly longer stirrup than what is shown in the picture. You know why? Cos it's bloody hard. It takes a lot of time to build up those muscles. Over time you get to the point where you can have your knees at wither height. If you tried to do that without conditioning the muscles your legs would literally give out from under you. And you would be introduced to the ground at high speed. Best to strengthen first.
Not only that but throw into the equation a rambunctious TB, a racing pad rather than a saddle and the odd barrier trial here and there and you have yourself an entirely different ball game to what is commonly accepted as two point. In fact even the stirrup position is different for trackwork, you simply could not have the stirrup under the ball of your foot, even for breezing it's usually slightly behind
the ball of the foot. Another great way to be introduced to the ground at high speed especially if you are coming out of the gates.
So whilst it could technically be considered a two point position that really is an oversimplified view. The exercise that MBP is describing is more like two point on crack.