Overwhelmingly, the response is that readers update edits.

That's really good to know. I was worried that some of my dunderheaded typos were making it to every one of your readers, and that you thought of me as a plain fool, and had documentation to back up your conclusions.

Ha. I can cover my tracks.

...Sort of. Zeeke42 gave the single most* helpful comment, saying:

"I get the fixed version on Bloglines. At the top of the post, it says: "UPDATED 5 hr 42 min ago POSTED 5 hr 59 min ago"

Aha!

I think that I'm going to sign up with Bloglines. Why not Google? Because I have two logins with them, and that could get messy.
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*Everyone's comment was helpful, and I thank you all for posting them.