Another bit of reading that might help shed light on the matter is
http://eznec.com/misc/Food_for_thought.pdf, written eight years ago
during one of the many times the subject has come up before on this
newsgroup.

The chart and discussion in the "Forward and reverse power" section show
that the concept of "reflected power" being absorbed in or dissipated by
the source is incorrect. I find the concept of traveling waves of
average power to be misleading at best, and analyses using this concept
lead to impossible conclusions like the supposed absorption of power in
the source resistance.

Roy Lewallen, W7EL