I was so excited that I'd found something for you that I didn't read the first part of the article carefully enough. Here's what I think based on the principles of canonicals and hreflangs as I understand them:

Since canonicals are meant to reduce confusion and duplicates, what could you do that would support that goal? If I saw multiple different versions of a product page that were essentially identical (perhaps they had different filtering options or search terms but resolved to the same content), then consolidating them all would make perfect sense. If, however, I saw two pages that had the exact same meaning but were in different languages, I would consider them as separate--you wouldn't accidentally mistake one for the other.

As for hreflangs, the second article mentioned 4 versions of the content and listed all 4 hreflangs. The idea is that the search engine could discover all the versions of the content quickly and select the right one for the searcher's language and location. I can't imagine there being a penalty for listing every one, either.

Have you had any other feedback (from outside SEOmoz)?