Sorry! Having spoken to @crokkon and @espoem and some people at Utopian the answer is that, whilst there are no curation rewards on the post, the author doesn't benefit. The curation rewards are simply not paid out (so they stay in the pool I guess). Not what I thought after all.
The thinking is that it's not possible to give 100% to the author under HF20, even if you are willing to sacrifice your curation rewards. So you're right, that is a step backwards.
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