"Please just use plain English, I don't understand what you're saying."

Looks like pure hallucinations just in a more poetic sophisticated register?

An interesting solution suggested in the replies (https://x.com/andrew_n_carr/status/2081534245370314816):

    The fix for this is to say: only report to me in ASD-STE100 Simplified Technical English.

I've had "tractable beachhead" a bit earlier today. Like in "the tractable beachhead was the coupling between X and Y".

A bit of googling did not help me, I have no idea what this is even supposed to mean.

Damn, I've been telling the same thing to Claude, good to know I'm not alone. I've also noticed that Opus 5 is much worse in this regard than Fable.

It's as if the model is speaking Mentalese, or in some "bag of concepts" language.

They scan too many classical literature.