Nope Swan doesn't give two F's about your mixing, they encourage it. However their Fiat Banking partner does care, as a matter of risk management against unregulated state agencies (FinCEN). A fiat bank doesn't give 2 shits about your bitcoin. That Fiat bank doesn't want to RISK (that word again) their entire business on a couple customers of a customer who the Communist/Statists have magically targeted as a "TerRoRisT!!"