(However, I've grown to learn that you and I rarely see things from the same perspective, so I fully expect a response along those lines yet again. 
)
"If everybody is thinking alike, then somebody isn't thinking." — General George S. Patton
The Series A White Lions were unique in that they were one of only two such print runs to have a color change mid-run. The purples came into being because during the print run on the blues, red ink was forced in behind the blue ink, resulting in the purple transition color and eventually in the remaining decks being red. Or perhaps the red was first followed by blue, but either way, the purple came about because of the color transition you mentioned.
The other print run to have this unique color change mid-run was the Bicycle Professional Skull & Bones Back in Air-Cushion Finish by CARC. They transitioned between red and black, resulting in a "blood red" transition color. Unlike Blaine's White Lions Series A, however, the red and black decks exist in roughly equal amounts while the red Series A decks were made in a short run - I don't know the exact numbers, but I think it might have been as few as a thousand.
In both cases, the color of the transition decks is not consistent, sometimes even on the same deck sheet, resulting in the backs having slightly different colors from deck to deck and in some cases from card to card within a deck. Additionally, the transition color was made in a series of only a handful of hundreds each, well under a thousand. I never got a White Lions purple deck, but I did see an uncut sheet of one at Blaine's office downtown, and I do have the blood red Bicycle Pro S&B Back deck.
I'd be surprised as hell if USPC ever did another such print run - I can't imagine it was easy to pull off, and I'm thinking the only reason the both of them were done was because of the connection to Blaine (he's a member of the CARC Board of Directors).
