[kossnocorp]

Yes, you got it right!

I'm also working on adding a delayed publishing like in GMail, so you can edit typos even before the thread got published.

[JoshTriplett]

Have you considered adding a very short link into each tweet (or into the first/second tweet), whose contents (as a Twitter card) could be later updated to provide corrections?

[kossnocorp]

I didn't. It sounds like a fun idea but not sure if the content consumers would understand it, and also Twitter caches the card content (not sure for how long though), so it might just not work.