I didn't notice or even really care about that, because

• the meaning was obvious

• I especially give more leeway on multi-regional forums where not everybody uses identical conventions

• I rank solidly in the mid-prole category of that quoted class essay, so I shouldn't care!

All in all, the article was speculative, but helpful. The essay was interesting, but woefully dated. I have the gut feeling that the essential points remain true but in a modern context not anticipated by the author. I got the impression that he was pointing out things that everyone may know subconsciously, but never would have pointed out publicly.