I think it still will work in those cases, as long as both entrance and exit is at the perimeter wall? And that it's the placements of those that determines if

I think it still will work in those cases, as long as both entrance and exit is at the perimeter wall? And that it's the placements of those that determines if left-touching is a viable option. For instance, it doesn't matter if it there's a freestanding wall/loop, as one wouldn't reach that anyway.