@JohnPhilpin Hmmmm... until now, I have resisted doing that, because the @micro.blog masto (technically speaking, it's ActivityPub not Masto, but calling it Masto for this discussion is fine) truncates at 280 characters, rather than the full Masto 500. My workaround is to syndicate from MB to Masto and then edit the syndicated post when needed.
But your solution might be better. And I can still post directly to Masto when I'd rather do that.
For literally the past 15 years, I've been publishing a lot of the same content to multiple platforms, and have wished there was a better way to do it than a lot of cutting-and-pasting.