I had a similar thing down in one of my mission betas...
The player was a platoon leader, and I needed to orientate the platoon's formation to the orientation of the player.
I used a pair of invisible H's that got alternatively placed at the player's position. Once the player was 20m away from one of them, I'd get the bearing between them and set the platoon's (read: squad's) formation at that.
This was good because the platoon would only change formation if the player actually positively moved in a direction. So the player could move around a bit (ie. find cover under fire) without the platoon (squad) re-forming back up...
I dunno... anyone interested in something like that? The player need never know it's happening, as all the components to it happen back end and are invisible...