I think there /is/ a consistency to a natural dialect or creole that comes across-- though Manglish might sound particularly natural to me because of my familiarity with some of the Chinese bits that are mixing in, Gullah and Jamaican Patois (those are the other two creoles I've listened to substantially large chunks of) sound real / natural in a way that bad translationese that poorly borrows from the original language's grammar does not.