Once again, all trails lead back to you providing some alternative solutions instead of the empty catharsis of coming up with downsides to something in an internet comment.
Here's one of my own: Isn't it annoying that spambots show up the second I launch a website? Ugh! Well, got that out of the way. Now I need a solution.
What's yours?
It's not about disliking anti-spam measures, it's about highlighting the woeful method that is re-captcha.
"Select all squares with street signs" shows a bunch of squares, some of them contain only part of the pole that presumably has a sign attached out of shot. So do you click that square that only has the pole? A pole is not a sign, it's a piece of steel. But it's part of the sign, so are people expected to select it or not?
Re-captcha is not a smart system.
Guess we can close the file on that one.