Don't just disagree, tell us why you disagree?

Yes you could say that pinion angle is centralized at the pinion / driveshaft. But every thing else determines your pinion angle. What type of suspension, soilid bushings, rubber bushings, ladder bar, 4-link, leaf spring and the angle of the driveshaft / engine centerline.

 

www.baselinesuspensions.com has some nice articles on setting pinion angle, instant center, etc...
Kevin Slaby seems to know his stuff and has plenty of cars running in the 7s using his items and techniques.

With solid bushings, you can run -1.5 to 0 degrees and hook.

 

I have discussed this with a local chassis builder, and he confirmed what my thoughts were.

There is no "magic" in pinion angle or additional traction based upon what pinion angle you run. It's simply a compromise so that under load, the suspension parts such as bushings compressing, parts flexing, etc don't cause the U-joint to go into a "bind" situation. People think front end lift and weight transfer characteristics changes with pinion angle, when in fact it's the control arm angles, attaching points, etc (talking rear only at this point) that change front end lift.