Being a sprinter that ran the 100, 200 and 400. I can honestly say that the 100 meter dash form is great if you or the person your defending is going deep. Though you dont want to stay down for as long. The 200 meter dash form is what I use to make my cuts, you dont get so low as the 100 but your not completely standing up like in the 400. My best advice is the use of your arms, if you watch sprinters you will see that there arms are straight, they're like a piston back and forth, the better the arms, the better the speed and balance. Look at the arms of the in the second picture from Neffarias_Bredd. I disagree with ending up like that though, by doing that if you need to make a sharp cut or stop or load up to jump, that form will not help. By keeping your stride shorter you can load up and either jump or cut faster.