No Bill, I thought it up all by my lonesome...
The prohibition just seemed odd to me considering that the pump seems targeted towards the enthusiast market, and at least some enthusiasts like to add bling bling color to their loops. (I've never understood the reasoning behind wanting lights and windows, let alone die jobs - they don't make a system cool better, OC more, or make less noise - whats the point? I'd rather spend the money on better kit)
I haven't studied pump warranties, but I've never heard of such a restriction. It would also make me concerned because an awful lot of anti-corrosives, anti-freezes, and biocides contain coloring of some sort, would they also be prohibited? I hear good things about the Swifty pumps, but if they are that delicate?
I would rather have a pump that can tolerate a certain amount of crud - anything intended for a pond or aquarium needs to be able to handle small amounts of particulate matter because it will be in the water (certainly larger particles than a good die would have). Hopefully a loop would be cleaner but I could still see possible contamination issues, and I wouldn't want a pump that was overly sensitive to them.
Gooserider