Just because your statistical sample of one doesn't do it, does not make the statement inaccurate. I fix pulls to one side all the time by centering the steering wheel. There is no assist to move the piston off of center in the steering gear until the steering wheel is turned to open the valve via the torsion bar. If the wheel is off to one side, the valve is open and assisting. It is that simple, that is how they work, that can't be changed.Are you saying that the power steering pump and steering gear will try to center itself if the steering wheel is not 100% centered and possibly be causing his pull to the right?
If so I would have to say that is an inaccurate statement. My steering wheel has been off since I bought my jeep and it drives straight down the road hands off the wheel as long as there isn't too much road crown.