Man, a buddy of mine ran into the same thing on a forest survey and his whole week of points ended up shifted about four meters off. He never caught it until a second crew walked the same units with a tape and compass and nothing lined up. So no, you're not slow, you're just the only one on that crew who learned the lesson before it cost him.

Same trail loop for me too, except mine is a 3 mile out and back near Boone. I saw a cub in a tree last spring about 15 feet off the path and didn't notice it until some guy behind me pointed up. Walked that same stretch probably fifty times before that and never once looked up. Now I catch myself staring at every oak like a weirdo. Started carrying spray in my hip pocket just to shut my brain up, even on quick after work walks.