Another startling phrase just, erm, came to my inbox: 'sexually progressive'. I thought it was a joke, but googulate it: this is something people actually say, or write, anyway, without any obviously ironic intent.
One might have thought that sex was something people had figured out rather well already, and quite some time ago. What progress is either possible or called-for? It seems unlikely that Elagabalus would have been too surprised by anything Craigslisters get up to these days.
But we live in an age of miracle and wonder, and presumably not to progress is to fall back. Excelsior!