Most NA regiments aren't very disciplined. That's why Locust and I structured the 40th like a European regiment; very strict.
I feel that these formations are used by regiments that are disciplined, but not very competitive. These types of formations wouldn't be very useful in a 1v1. And rightfully so, both NWL and NANWL don't allow/use them. They can be enjoyable in events like Beech's, as you stated, if done properly.
I could be wrong, but the 1stEPI was never in NWL and they always use these formations.