Hi
I think that the Neutralec wasn't considered viable to sell to customers on the off chance that shading may occur. Rylux Carpets were involved in a great deal of research surrounding shading, and they pioneered carpet that would not exhibit shading by setting the pile angle to such a degree that there was no way it could fall any other way than the natural pile direction. I believe this system of manufacturing carpets was called the Trutrack.
Other research was done on the correction of shading which I believe was limited, but had some success using steam to reset the pile. The problem being though that you have the natural pile direction and then the alternate pile direction, but then you have an in between no mans land where the pile has burst into every which way that clearly nothing can be done to rectify.
Often you may see specific non foot traffic shading running over doorbars on to different types of carpet, and following on to rugs as well. This is one clear indication that Shading is attributed to something other than a fault in manufacture.
Regards
Robert