Hi Dan. Interesting article.
I come from a POV that does not disagree with the concept of blocking. It has it's place in the defensive heirarchy, although it's at the bottom of my list. Evasion is at the top IMHO, owing to maximal efficiency. It allows for instantaneous defense AND offense.
Parries are next on my list. While they limit offensive options while you are doing them, they do afford control of the opponent's momentum, and thus his weapons.
Blocks are the last resort, as they give you very little control of the opponent's momentum/weapons. Neither do they allow for good offense.
Now, I am working from these definitions:
BLOCK - Force on force stopping of incoming strike on a +/- perpendicular angle.
PARRY - Redirection of opponent's striking momentum on a +/- parallel angle.
I note that many of your "blocks" are actually "parries" by my definitions.
I did like that you stressed blocking applications above the elbow joint. We were trained to do that in American Kenpo, as well. I think it does afford much better control of the opponent's arm and overall momentum.
I disagree with you about the usefulness of the MMA shell/helmet defense, but appreciate the effort made in the article. Well done.