I would never have thought of precession as an approach to this problem, but this seems to be a very interesting train of thoughts.
I'm still wondering, though, why Boeing would simply ignore that effect and stick to this "If the airplane is properly rigged, this should result in an approximately neutral wheel" - statement? My observation has been that because of this statement most pilots trim the wheel to the neutral indication, resulting in some very small, but still noticable bank. In the strict sense, this could be called "uncoordinated flight", which is definitely not what we are aiming for in terms of fuel economy and airframe stress. I know that this small out-of-trim condition will not bend the airframe or increase fuel consumption drastically, but I still find it peculiar that it is simply being ignored by the manufacturer.