I'd not read this page before. Quite engaging. What might have happened if... for example the North Eastern had electrified its mainline to 1500 V DC... or the Western Region had won the argument about hydraulics versus diesel-electrics...

http://www.kalyr.com/railways/LocoTimelines.html

Cheers, NeMo

Nice ideas for rule 1 layouts in there. For myself, Rule 1 applies and I'm planning a Doggerland layout set in what we call the North Sea and with rail links between the UK, Germany and France.