Originally Posted by
the810
This won't be easy to change as UK airports aren't really designed to let people out of the plane into a departure hall, because if you do that, there's no public path for terminating passengers to exit.
That's one of the reason why the security should happend in the Terminal you arrive. Then is the inter terminal connection much easier and you wouldn't have to separate any passenger flows. Airports in Schengen have two parts. A Schengen and a Non-Schengen part. Maybe UK should think about to have domestic and international parts. In my opinion today it is just a mess. This would need a complete remodel of all UK airports.