We use a fixed block system - one train, one time, one block. The continent and other places use what is called moving block which I am not completely familiar with. This is not compatible with fixed block so would require a whole new signalling system.
Yes, that's what I was referring to. When I worked in Switzerland the guys used to tell me how much more efficient the European system was, allowing much higher traffic densities, but I really didn't understand how it worked other than it would need major changes to the UK systems to enable it.
