I decided to look at the page in Osterkamp that Leigh used for her formula. Going there I discovered three formulas. One of these is the one that Leigh used.
I did the arithmetic with all three formulas. And I multiplied each of those figures by 60% to 65% -- the percentage of maximum sett when weaving clothing or with woolen yarns.
The final sett turns out to be somewhere between 5.58 and 6.04. 6 it will be, the same as my original calculations, as I said in Part I.
WASHED VERSUS UNWASHED HANDSPUN
I thought of something, then, that made a difference in my feelings about using 6 as a sett for this yarn. Before I washed the plied yarn, it was really quite thin. But when I washed it, the magic happens: it blooms! And when it blooms, it takes up space. The wpi of the unwashed plied yarn was 19. Contrast this with the 13-14 wpi of the washed yarn.
I am not quite so worried anymore...........
Related Post: Handspun & Computing Sett: Part III