What?!?!? That makes no sense genetically! If that's so, why was Steve selling Spiders Het Pied and Spiders 66% Poss Het Pied last year? If what you're saying is right, there'd be no such thing as a Spider Het Pied (which makes no sense). Please explain!
Even if you breed a Spied to a Pied, you'd still get 50% Spieds and 50% Pieds, not all Spieds!!