Originally Posted by
Mark Kelly
The part that is often missed is that since maximal spoke tension is proportional to cross sectional area which corresponds to mass per unit length, you can replace the mass per unit length in the pitch equation with a constant, so pitch at maximal tension becomes
F1 = K.SQRT(T) / 2L
where T is spoke tension and L is spoke length.
Since there's less than 6% difference between common 700C spoke sizes there's less than a semitone of pitch variation amongst them at maximal tension.
You're right that the same pitch will translate to tension in proportion to spoke diameter. And many old timers including myself will factor diameter, in setting our target tensions, but most builders today don't, and try for the same tension range regardless of the spokes used. Moreover, old timers that do factor gauge tend also to factor rider weight and other variables, so there's no magic number or pitch, though there's room in the ballpark.