On 1 May, between East Putney and Southfields, two District Line S stock trains clattered into each other - or, in management-speak, "came into slight contact".
The cause? The tracks in the area had moved. Again in management-speak, this was a "slight movement", but if it was enough to cause two trains to hit each other, then even if it is "slight", it is very very serious.
You may wonder how an incident like this would have played out if there had been no drivers on the trains. And you may wonder why track is moving and whether this might just having something to do with management reducing the frequency of maintenance and checks.
Management should stop talking down serious incidents of this type and instead reverse their cuts in track maintenance frequencies and abandon plans for driverless trains.