I see constant references to overlays and AFCAD. It appears as if overlays are used to make AI planes go to specific gates in the airport and use specific runways. I also guess that this has nothing to do with visuals, only with traffic routing around the airport.Can someone explain this a little for me? I haven't had much luck figuring it out. For example KLAX is my home airport but there seem to be many "overlays" and they all seem to be using different approaches to it.How does it all work, and what are the benefits? Is it hard to implement? How does it affect the way you create flights, land, taxi, etc.?Thanks for any assistance

Consider KLAX with two parallel runways per side. Using overlays, you could have the North Side use one runway for landings while the other is used for takeoffs. Similiarly, the South Side uses its corresponding runways.Secondly, the aircraft using the North Side can be made to taxi to those gates on the North Side. The South Side does the same thing.There are any number of ways to skin the cat!! It is whatever your preference happens to be.