I went to Blogger address provided by 01 Doc in a previous comment. I queried Blogger why I could not comment on Sarah's blog. I said that Blogger could reply to my gmail address.
THEN, I signed in to the Google gmail address found a copy of my query to blogger which had been sent to gmail. That email contained the url for Adventures in Lake City.
I clicked on the url, was transferred to the actual blog and was able to comment. Why? I dunno. The Universe moves in mysterious ways. So does the Bloggerverse - possibly the Google-verse, too.
I do know that I had better not delete that email, ever . . .