Talked to Vaughn via e-mail. Apparently the study used this product:
Nmda by Muscle Warfare - Buy Nmda 90 Capsules at vitamin shoppe
Look around the net at the reviews on this stuff and you'll find most are disappointed, whereas you have quite different and more positive feedback regarding Intimidate, which has a 99% purity rating. Apparently Muscle Warfare is known for using bunk/junk ingredients.