Just for kicks, I asked 3.5 Sonnet to write some sentences that didn’t exist in its training data. I googled the output and sure enough they appear to be unique. Most were semi meaningless strings of words, but I thought this one was quite poetic:
“Vintage umbrellas hosted philosophical debates about whether raindrops dream of becoming oceans or if puddles remember their cloudborn youth.”
Oooh that is very surprisingly nice! "cloudborn" is a great word there, how lovely, it slows you down at the right moment for a little explosion then at "youth". I wasn't expecting a genuinely excellent answer here :)
So it turns out then that the trick may be to find a way to get them to avoid aping the oceans of human mediocrity they've been spoonfed! Funny, it's the very same reason some poets go off and live in the woods.
“Vintage umbrellas hosted philosophical debates about whether raindrops dream of becoming oceans or if puddles remember their cloudborn youth.”