From: Somewhere deep in appalachian valley in PA
Those issues are coming from traffic due to bridge and winding narrow road during March formation. I saw that if first car stops to make a turn, the second car stops and sometimes try to find alternative way, that makes chaos and delay. This happens when there is a bridge and unpassable water, or when marching column should do multiple turns to follow the road. Vehicles trying to find alternative route, then attempt to go around, which results funny yet dangerous route finding.
Large spacing between vehicles would help, but still sometimes happen. Plus, as far as I know, devs are trying to improve this, by allowing 2 or more multiple units in single 30m x 30m basic unit cell. That will help to reduce those behaviors.
Also, I usually don't use march formation in the field. I only use march formation in city, only when there is no enemy nearby, and preferably on highway. I found that AIs feels more easy to find a good route on highway.
This is one of the reason why platoon is better to maneuver than company, especially for AI. Human can fix this issue, but AI feels hard to fix. If you want to set up challenging AI, consist AI force with platoons only, that will help a bit.