Barely any app devs as far as I’m aware implement nip-66 relay liveness checks e.g. for outbox.
Nip-66 reduces feed loading time by ~~40%.
https://github.com/nostrability/outbox
nostr:nevent1qqs...
I do like the idea of adding a bit more randomness to publishing events. Like having five randomly-selected relays from a curated/tested list added every time, as a client-option that the user can turn off.
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