[desufnoc]

I can't imagine somebody would trust me with their root-domain, basically.

The “root-domain” is the domain name with a single zero-length label at the top of the hierarchy. What you're referring to is a zone.

[stevekemp]

I thought context would make that clear, but yes you're correct.

[desufnoc]

Yes it is from the context that I inferred what you're talking about. I didn't mention it to pick, but because the DNS is littered with misunderstandings and I think that's part of what holds it back.