My issue isn't that it does or does not highlight an area, it is that sometimes it highlights an area that is not a building and the instructions are a bit vague as to is this is "correct" or not. One example - I see it highlighting someone's back yard with a swimming pool. It is not a building. Is this correct or not? I mean,it has identified the shape perfectly, but it is not a building. I feel like lazy people clicking through CAPTCHA is not the place to make important decisions on OpenStreetMap map level features without a lot of filtering of the results.