That Luxembourg course is pretty intense!
They should have cut the line between 11-12 to better show the gap in the uncrossable wall along the best route. Neither of the two routes posted took that route. It took me a sec to understand the control description for #18. I actually looked at it on Google Maps to make sure I was understanding the map correctly there.
I didn't even see that gap until you mentioned it!
Yeah, I've learned a lot from mistakes I've made, so I notice things like this.
I'm usually pretty OCD about cutting lines and circles but there was one instance recently where I could have done it a little better. I forget which event it was for, but it was a very similar situation to the one on 11-12. In my case, I don't think the line was obscuring anything, but it didn't make the gap obvious to see.
The recent one I was thinking about was SART Time Trial, #1-2, the gap in the fence west of #1. The line isn't obscuring the gap, but I guess it makes it a little harder to see. This was feedback I got from runners, and I definitely saw people run around the gap.
But I'm sure I made an actual gap-covering mistake before, though.