Kerf and a circular saw?
In the article you said there was a notch to follow for the kerf yet in the above photo you're not on that notch. You nailed the cut correctly though. Is it more of us learning our saws? I learned something new with the Kerf. My son and I made a bird house this weekend and our cuts were off. We made our measurements first then cut the board. The bird won't mind but lesson learned.