Hmm. Well, I read 90% of the article and then the comments on it.
I agree, the author was probably wrong to title this article with "collection" in it. While this article is not the greatest source of how to collect a horse, it does have some very useful exercises to help achieve a horse that is collected at any level. Some exercises are not as great (the evading the bit exercise made me raise an eyebrow. The only thing it MIGHT be useful for is developing muscles, but this can be done without the bit and on the ground.)
I have minimal if any Dressage experience. Please correct me if I'm wrong.
"The wise man thinks he knows nothing.
The fool thinks he knows everything."