Excellent. Note that although i might have preferences on what is out in the alt-tag, it does not really matter all that much, anything is better than it not being there.
Combine it with nip89 and Nostr as a whole functions so much better.
This way you can always just reference whatever event in a kind1 note, and be rest assured nothing breaks and is at worst, suboptimal. Also takes away pressure from kind1 clients to keep up with stuff if they dont want to.