"Does not matter if you nock taper before or after tail taper if the taper tool is made correctly."
I would say it depends on the taper tool, but I don't know of any that it wouldn't affect. For example, I use a taper board against a sanding disk on my table saw. If I do the shaft taper first, then the angle is changed when I run the shaft along my taper board to cut the nock taper on the sanding disk. Probably less than a half a degree, but it changes. To guarantee the same angle, I have to shim the shaft taper just before the nock, 1/2 of the diameter I reduced the shaft. For example, if I go from 11/32 to 5/16, that's a difference of 1/32. Half of that is 1/64, the thickness of a piece or tape out two for a shim near the nock end of the shaft.
With the pencil sharpener taper tools, if the shaft is already tapered to close to 5/16, it won't fit into the 5/16 chuck/ferule, and it will be a tad loose in the 11/32 chuck, potentially yielding an uneven taper.
Just a lot less trouble to cut the nock taper before the shaft taper.