if the german 88 with its lage shell size has an historical ccuracy up to 4000 or 5000 meters (but a 2000 m effictive range for tank killing ?), and we now have maps at historically accurate sizes, it would have neem interesting to see how accurate the game engine is in moddeling shells being fired at that range (by manually controlling the gun and firing at a known target). simply put, if you can adjust the gun manually in game, and you know the exact location of the objective you are firing on, then in the game it should land exactly where intended.
somebody here on those forums had reall life experience in a tank unit, at least 2 others in the flightsim forums i know have been in an artillery unit during their military service, it would have been good to see their feedback on how accurate oleg's sim is
it is much harder to do with aircraft firing at an object (because the aircraft is moving, and the shells are much smaller), similarly dropping a 250 kg or 500 kg bomb is a bit harder to compare with real life behaviour because it just makes a big bang and you cant trace the trajectory so easy.