They do not admit it because these types of flights happen only under very special conditions as posted by almost everybody. If you'd ask me for a guess, I'd say that one hand should be sufficient to count those instances for a given route.

And jimpop, with all due respect, this is not about an opinion; it is about a fact. And fact is that those double-crew flights are not regular procedure on any of those routes listed, and especially not on the MUC-ATL flight on which Hub Flyer did not receive his upgrade.