Isn't the obvious - and from the above legal - workaround that if you are flying the same routes you will be on the same frequency anyway.
So when aircraft 1 reports position ("G-ABCD overhead Anytown 2000 ft") you'll know where they are.
I appreciate that means you can't exchange pleasantries on the view or insult each other's takeoff skills but...then again maybe that's a good thing.