Whats the purpose of the broadcast function?

Same like reposting? But not to your feed?

#asknostr

Does this republish to failed relays on my end?

nostr:npub1gcxzte5zlkncx26j68ez60fzkvtkm9e0vrwdcvsjakxf9mu9qewqlfnj5z

And when amethyst finally intergrates with NIP-65 would this help to get my notes to my followers relays published? Since i might not be connected to the same relays their using.