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I did it from Ebbsfleet-Brussels with a DB print-at-home a couple of years ago, but haven't done it on more recent trips, as I was using Interrail tickets+supplements.
Yes, however given the recent Ashford conundrum it appears, as a colleague of mine travelling on one of these found out, if they change the trainset you don't get a new seat on the new one - which seems to be ever frequent given the Ashford issues.