Emphasis mine.
If you’d like to write a Scrivener alternative with this feature, feel free. After all, Scrivener itself was created because the author didn’t like the existing tools.
But Keith has been pretty clear that he doesn’t see this feature as feasible or desirable within the existing Scrivener codebase. On which, as has been noted, he is the world’s leading expert. Popping in every few months to talk about how easy it would be is unlikely to change his mind.
Katherine