AllenR,
listen to LBR - back twist is the only way to make a round string (-body).
The loops will be rounder and smoother with 3 bundles. I prefer 3 bundles mainly for this reason but think it does also hold more tension in it's splice. There is more contact and "mixing" between three then two bundles = more friction. Though, with modern materials a two bundle string with splice made long enough will suffice almost any time.
Three bundles can look nice with the possible color combinations but are little more work, of course. I've posted the pic below many times because it shows all these aspects in detail quite nicely:
Twisting until it starts to kink is nonsense IMHO. The main body of a string should not be twisted to much. In theory, parallel bundles would make for the highest performance due to less mass and coming to a stop at brace height - all at the same time.
When I do a string I try to get correct lenght with close to 1 turn to an inch. Not because the string would need it to hold together but simply because it can thus made a little longer, if needed, by untwisting. Applying more twist to shorten it is seldom a problem.
I rubb the string with a piece of cotton cloth until warm. I would burn my fingers if I rubb to much. Good so! And the cotton will suck any surplus wax of the string - I don't want a candle - just enough to lubricate it ...