The people who have reservations about insulting random people on the street, or farting loudly on a crowded bus, are likely going to have reservations about recording people whether there's a light on or not!
That is absolutely true, which is why the original article was about etiquette, not somehow creating supertechnology that can restrict a Glass user from doing bad things. That is, the LED is about feedback, not restraint.
My comment is about the suggestion of lights as a technical solution in past comment threads. It's not about the etiquette suggestions in this article.
And you can insult random people on the street, or repeatedly fart loudly on a crowded bus.
The article is about etiquette.