I've lost count of the number of times I've suffered WCML disruption due to broken down class 66s, Voyagers or older freight locos. Voyagers have a, ahem, track record of doing little things like ingesting water through their exhaust vents, or catching fire.
Everybody on here knows the advantages of electric traction around operating costs, track wear, reliability and so on. Not to mention the problems with diesel fumes at enclosed stations. Ever walked out of the underground at Marylebone and been hit in the face by that smell? I'd be interested to know if travelling from Marylebone causes a higher occurrence of respiratory disorders.
OHLE problems on the WCML do usually happen in the same places and there may be a need to reintroduce a 110mph speed limit over locations like this just to prevent this sort of thing happening. But that would have obvious impacts not just on journey times but on the entire timetable for all services.
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