Why the option to adjust ingress and egress?

[MarkShot]

I understand why you want to steer an AD around known flak sites or assumed sites (like enemy units and cities), but the ability to split ingress and egress? Is the OPFOR AI assuming that you are going out the same way you came in? Does it get a bonus hitting you during the outbound legs if they don't vary?

All things being equal, I am thinking one route in and out for all near missions might be advantageous. Why? When the enemy runs out of miles, they will stop coming up to meet you.

BTW, I was playing around with some ground stuff and erased all my ADs and naval in the DOCTRINES; so, I could speed through the air phase as the Germans. Well, my forward based fighters were quite aggressive flying over the front to intercept Red AC like air freight. (Just like someone had said here that this may be more effective than flying superiority ADs; especially with the high op loss rate.)