Should point out that historically trains used to run on Cristmas Day and Boxing Day.
If the BR levels of pay (with allowances) remained to this day rather than the payment levels of today how many of you would be working with the large amounts of overtime payments etc that no doubt would be on offer?
What BR did or didn't do is a rose tinted irrelevance.
BR could get away running trains in the days of yore because:
1. They ran far fewer trains, so it was easier for us to trample around the cess and four foot, digging holes, erecting masts, putting in drains or running signalling cabling without being bowled over by a train every 15 minutes. We forget how few services BR used to run - on some routes it was one service an hour, one every two hours, which was probably one service every four hours during Christmas. We would be running services every 15 minutes, 30 minutes max today on those routes, I reckon.
2. They could divert trains, with freight (no heat) locomotives able to drag the leccys away from the WCML when it was dug up. Now, there's few paths on diversionary routes and running stock with no ETS is unsafe as it's all power doors, power toilets and power safety kit. If you could divert it with the two dozen Thunderbirds, you need route knowledge, which doesn't exist because for the other 360 days a year, you ain't diverting anything over other routes as there's no paths.
We could kill the OLE for maintenance and stick a diesel on the front of a leccy service and drag it through the dead section with no trouble. You're not doing that with a dozen Virgin and LM services an hour, you could with a couple of BR services.
3. We didn't care about H&S. In combo with 1&2 - less trains, diversions etc, we were quite happy to have guys up ladders installing OLE with trains passing underneath (albeit cautioned past). We had cherry pickers from roads and sidings to get guys up masts fitting OLE. You could install a mast base between a train, not because mast installation was super quick, but because trains were so infrequent. Three or four hours to dig holes, do shuttering, mix and pour concrete, load spoil into wagon, shift to next site, all without having to worry about a train for ages.
It was even possible to unroll fully prepared headspans between trains, get them up the masts, tensioned and pretty much ready for contact and catenary wires between trains.
It really was very, very different back in the days of BR. Trying to do maintenance AND run trains today, with the work we need to do, H&S requirements, volume of maintenance required etc, is virtually impossible. 54 hour possessions are needed sometime, people know the railway can't do much for a handful of days a year, I think in light of what needs done and how long it takes to do it, shutting down now is the most sensible of ideas.