@jangell2: My bad, that wasn't terribly clear.
Yep, all of this applied to CM's sync behaviour, be it export or import. What I should have said instead of CM managed is Calibre managed, you get the idea

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As for your last question, if you happen to have a Calibre collection matching a preexistent 'Kindle' (meaning not managed through Calibre, *right now*, but, indeed, who created it in the first place doesn't matter) collection, the Calibre one 'wins' during the sync.
On the other hand, if no Calibre collection matches that 'Kindle' one, it'll be left alone, untouched.
TL;DR: Which is why I didn't really think getting into the details would help ;D. Just saying "CM never deletes a collection on import" pretty much sums it up perfectly

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