@mudgel - yes, I understood what you meant. Thanks. It would be crazy if it did anything to the sound without asking. But apparently digital DAWs do not escape all issues analog mixers have. So summing a large number of tracks still adds noise, even in digital. Could be they added some clever algorithm to reduce that - not inconcievable.
Anyway, I'm sure if they had, then they would have trumpeted it from the rooftops.