Interesting thoughts. I also tend to view it from the perspective of a commercial operator (which A519 is). Looking at it that way, I don't see how it is feasible to use tape for this process. It would take too much time to mask in any quantity. Plus, the way the edges look, I came to the opinion that it wasn't tape.
I also thought about creating some kind of stamp or flexible stencil. My best guess right now is some kind of 5 spoke flexible thing on a stick that is sprayed or dipped in white then placed in the mold cavity and then turned a few degrees. IF you look closely at the white stripes, you can see some horizontal lines that suggest movement. Seems like a possible way to do it - I'm just not sure what to make the tool out of.
@keychris when you say to spray the red, then apply white with a finger....do you let the red dry completely first or do you let the red and white mix to create the color variations?