I would not wish to argue with the esteemed members of HM's finest Royal Air Force, but there is surely a difference between flying a formation with the wingtips practically touching (the kind of stuff which is done for magazine front covers), and flying a few hundred feet apart when quite reasonable pics can be obtained.
The latter obviously still needs careful organisation so one aircraft reaches a waypoint and loiters there at an agreed altitude, and then the other one departs and reaches it 500ft lower down, after which one can depart along an agreed track, sits there on autopilot, and the other one climbs up and does a flypast.
The camera is on the first one (the one on autopilot).
In the simplest case, the plane doing the flypast needs to do the flypast to the north of the camera plane so you use the light to your advantage.
The result is not magazine cover stuff but is very adequate (
example example) and would have been better with a decent camera; these were taken with a 3PM stills mode of a camcorder.