Perhaps, for once, we have reason to be thankful that they did close Wigston - Rugby, otherwise Beeching and his acolytes could have left us with even bigger problems than they eventually did.
Well, ironically enough, I think it could have proved to be a good thing in the end. Let's say the Midland route had survived until 1966. BR planners, wide eyed at the possible 'savings' to be made, suddenly realised that they could divert all Midland main line trains into Euston via the pre-1857 route. So they get the plans together to electrify at least to Leicester as a first stage (don't want to block up Rugby changing locos, and need a fast timing to Leicester to sell the move to the public).
The modernised, electrified Rugby - Leicester line opens in about 1971, and a 1TPH Sheffield - Euston and 1 TPH Nottingham-Euston (stopping at Leicester and Rugby) is initiated. Cl 45/1s take over trains at Leicester until Phase 2 - electrification to Nottingham and Sheffield is authorised.
But you can't actually close the 'old' Midland route to Bedford entirely. You have to maintain a 1 TPH Leicester-St Pancras service for the citizens of Mkt Harboro, Kettering etc. (Bedford to London is safe as a commuter line, of course.)
But you would go about singling Wigston-Bedford to save costs - in a Salisbury-Exeter like operation.
But this would take time. Meanwhile: the original 1966 WCML timetable - remember, outside the peaks, this was a mere 1 train per two hours to Liverpool and Manchester - has steadily attracted more traffic. By 1973 or so, you actually want to start 2 TPH Euston -Birmingham instead of just 1 TPH (I remember the shock on seeing that revolution!)
Before you know it, I could see plans being reversed, as BR realised that the WCML did not want to provide paths for the diverted Sheffield and Nottingham trains - it would need every path it could get for its traditional services. The rationalisation of Wigston-Bedford would be stopped, and, somewhat red-faced, BR would reinstate Sheffield-St Pancras trains, perhaps by c 1980-82.
Meanwhile, you would have a nice alternative, electrified route from Leicester to Rugby. OK, they might dismantle the overhead to wire some of the traditional Midland line, but I doubt they would have closed it. End result, you still have a well-maintained Liecester-Rugby line - even if only for a 1 TPH DMU shuttle back then.
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