It would be especially helpful if I could do this while editing an Implementation. It wouldn’t need to be connected automatically but that is worth considering too (as an option).

Probably a separate request but I thought I’d mention it here first: it would also be useful if we could save an existing test case as a new one, while editing it (leaving the original unchanged). Not quite as useful, but perhaps more intuitive, would be the ability to duplicate an existing test case and amend it before publishing it.