Jim Kelley wrote:
"100% wave cancellation means 100% energy reflection."

That's a no-brainer when quoted in the context of an
RF transmission line. Shame on you for once again quoting
something out of context. If it happened in space, it
would say, "100% wave cancellation means 100% energy
redistribution." as explained on the web pages below.

There are only two directions in a transmission line. If
energy rejected by a mismatched load doesn't make it to
the source, in a lossless system, it must necessarily
be 100% re-reflected. Rho^2 is reflected by the impedance
discontinuity at the match point. That's step one. Step
two is that 100% wave cancellation. Given those two steps,
no reflected energy flows toward the source. Therefore,
it must necessarily have been re-reflected back toward the
load. Since it joins the forward energy wave, we can
measure that is exactly what happens. It's a no-brainer.

Here's the in-context quote.

The destructive interference energy resulting from wave
cancellation at an impedance discontinuity becomes an equal
magnitude of constructive interference in the opposite
direction. Since there are only two directions in a transmission
line, wave cancellation is the equivalent of an energy reflection.
100% wave cancellation means 100% energy reflection. [9]

[9] Quotes from two web pages from the field of optical engineering:

www.mellesgriot.com/products/optics/oc_2_1.htm

"Clearly, if the wavelength of the incident light and the thickness
of the film are such that a phase difference exists between reflections
of p, then reflected wavefronts interfere destructively, and overall
reflected intensity is a minimum. If the two reflections are of equal
amplitude, then this amplitude (and hence intensity) minimum will be
zero."

"In the absence of absorption or scatter, the principle of conservation
of energy indicates all ‘lost’ reflected intensity will appear as
enhanced intensity in the transmitted beam. The sum of the reflected and
transmitted beam intensities is always equal to the incident intensity.
This important fact has been confirmed experimentally."

http://micro.magnet.fsu.edu/primer/j...ons/index.html

"... when two waves of equal amplitude and wavelength that are
180-degrees ... out of phase with each other meet, they are not actually
annihilated, ... All of the photon energy present in these waves must
somehow be recovered or redistributed in a new direction, according to
the law of energy conservation ... Instead, upon meeting, the photons
are redistributed to regions that permit constructive interference, so
the effect should be considered as a redistribution of light waves and
photon energy rather than the spontaneous construction or destruction of
light."

Note from W5DXP: In an RF transmission line, since there are only two
possible directions, the only "regions that permit constructive
interference" at an impedance discontinuity is the opposite direction
from the direction of destructive interference.
--
73, Cecil, http://www.qsl.net/w5dxp