It was also a bit of a mystery to me how that valve worked as I never found a diagram. Suffice to say, we didn't keep it on the car because
a) we really couldn't detect a statistically significant effect with it installed. We had the "before" data - fried brake calipers and burned up seals, and the "after" data - fried brake calipers and burned up seals and
b) we were not 100% certain of the valve's legality in the SCCA Improved Touring class.
In the end coating the pistons with a ceramic heat rejection coating, using some high buck seals, and improving our ducting designs really took care of our braking problems.
YMMV.