Sry I should have said generate npubs from an xpriv. It might be a bad idea, but it could be interesting to experiment with trust models where you give an xpub to a relay or some service, and use the corresponding xpriv to generate new npubs each use
Discussion
Like fiatjaff said, if you leak any of your privkeys they all get compromised to the relay who has the xpub. Probably not a good idea. I think maybe a reference to a list of pubkeys would be practical enough
Leaking privkeys though… obviously this is bad in any scenario. In the context of nostr, I’m not sure what the specific concerns are with providing an xpub to a service provider. To me it seems equivalent to giving an xpub to a Bitcoin exchange, etc.
I’m not promoting the idea, just trying to think it could provide any UX benefits to nostr relays/services