Excellent post. The only thing I'd like to see changed is the removal of "There are those who are of the opinion" about clutch wear in the rev-matching section and synchro wear in the double-clutching section.
To me, that's kind of like saying "There are those who of the opinion that the earth is round".
Rev matching absolutely saves wear on the clutch. It's not an opinion, it's an easily demonstratable fact. Same with synchro wear using double-clutching.
The only question is whether saving the wear is worth the effort. Most people don't care if the clutch lasts 150,000 miles of normal use, but would last 200,000 if they rev-matched every downshift. Same for the synchros.