When is a 48 hour strike not a 48 hour strike?

When it's a strike on the London Underground. The official strike is planned to run from 18:59 this evening and run until 19:00 on Thursday evening. However all London tube users know that services start to run down an hour or more before the strike starts "to ensure trains are in the right places for when the service restarts" and only gets back to normal the day following the resumption of service. In addition because the Underground service start to run down before the end of today's working day, people's work and travel plans are disrupted for the whole of today

So a 48 hour strike really affects people for three whole days. If the RMT wanted to minimise disruption to a 48 hour period then the strike would run from the start of one day to the end of the next - 2 whole days, albeit not 48 hours - more like 45 hours. But then since when did the RMT care about inconveniencing the public? Odd that the start of this strike coincides with an England football match, I seem to remember that happening before...