My bridge/obstacle crossing tactic
Here is how i cross bridges/obstacles, without the AI getting wet.
See attached picture for better understanding.
1) Create a route from WP1 to WP2, end the route by right-clicking on the mouse, set the formation to whatever you like.
Remember to place WP2 atleast 100m BEFORE the obstacle/bridge.
2) Right click the mouse on WP2, and continue the route through the obstacle/over the bridge, order Column formation.
3) Place WP3 AT LEAST 100m AFTER the obstacle/bridge, and order any formation you like.
If done correct, the AI will drive in combat formation from WP1 to WP2, then change to column formation, drive through the obstacle/over the bridge, like ducks on a row, and then at WP3 change to combat formation.