Nat, one of the readers asked me what the design I showed you (the third design diagram in this post) actually looks like on a real thimble and here it is. This is quad-coloured scales, or period of four scales. Although it's one of the scales design, the separate name of "arrow's shaft feathers" or just "arrows" is given to the design. The design looks nicer when the angle of the thread is sharper although sharp angles require you to space your stitches with care.
I tweaked it a little so this is no longer a arrows design or scales. I miscalculated a little (happens a lot) and it didn't turn out the way I thought it would be, but this is not too bad, if I may say so myself. I will see if I could refine it a little.
By the way, what do you think about calling a period of four design as a quad-coloured scales design when it is stitched with only three colours? The same issue arises in Japan, too, but no one has not concluded what is what. "A period of eight scales in four colours" is more accurate and clear to understand, on the other hand it is not easy if you do not know what the period means. What do you think?