Is it just me, or does GPT4 respond better if questioned about content that might contain an error, without pointing out the error? Inevitably, if I accuse it of an error, it gets tied in logic loops much more quickly (flustered?)

Yep, it's called chain of verification (CoVe)

Yep, it's called chain of verification (CoVe) https://paragraph.xyz/@metaend/chain-of-verification-ai-self-check

Co-Founder 

Contact: https://alice.chain.box

Are you saying the "nudging" the model vs. direct confrontation has a measured, predictable benefit?

Depends. If I know there is something missing for example an import in a react script I tell it "I think xyz is missing", but if I don't know exactly it's better to make it double check. IMO