[JimDabell]

You could say that a lot about how web components work. If you want to see some of the mess in sorting the spec. out, check out the discussions in the csswg-drafts repo, for instance:

https://github.com/w3c/csswg-drafts/issues/1915

https://github.com/w3c/csswg-drafts/issues/6466

https://github.com/w3c/csswg-drafts/issues/10094