The original article was specifically about reCAPTCHA, not homebrews, and how difficult they now are (something I've also noticed lately). Either give it a (re-)read, or if you're saying you were able to easily read the examples in the article please share the answers! :)
ReCaptcha only requires one (1) out of two (2) words to be correct in the challenge.
It presents one known-by-the-system-word, and one not-known word. If you get the known word correct (the easier of the two to read) then it passes the challenge.
ReCaptcha then pools the answers for the second not-known word and after pooling thousands (or more) responses, then that word becomes "known" based on the average answers (and then that word is "digitized" and used by google maps, or ebooks, etc).
Again, sorry, I've got to point you back to the original article. The author explains the details of reCAPTCHA's known/unknown word-pair clearly, as you have done, but goes on to explain that the impossible-to-read word was actually reCAPTCHA's "known word", so the CAPTCHA was impossible to pass.
Yes, but the author actually only tried once. Every other example he gives, he claims he hit refresh to get a new one instead of attempting it.
Also, I have to wonder if he was simply mistaken about that first attempt. Are we sure it didn't just fail because his username/password was wrong and display a new captcha, causing him to assume he had failed the first captcha?
I do have to admit most of those are cases where both words are difficult or impossible. But we can at least assume that the easier of the two (the one not cut in half) is the control in most of those.
