Ah. page-break-after. So I could make the multi-story chapters as suggested by DSpider, with "page-break-after" between the individual stories. Kewl.
I don't know of any desktop ePub reader which honours pagination.
Well, ADE seems to, so I (perhaps unreasonably) expected that other software would do so as well. As I'm sure has been said thousands of times, would be nice if all software and devices strictly followed the same standard!
Thank you, Alex. I'm off to experiment.