Dave wrote:
yes, superposition is meant to work directly on voltage, current, electric
fields, and magnetic fields. it can be extended by adding appropriate extra
phase terms to power or intensity as cecil prefers to use.

That seems to be common knowledge except for some
(narrow-minded?) posters here. Powers do not superpose
but there is a method of adding power (densities)
that has been acceptable to physicists for at least
a century and may date back to Young, Fresnel, and
Huygens.
--
73, Cecil http://www.w5dxp.com