Cinematically mobile in the curved underworld of greater London

It's interesting: videos like these – made by Tube drivers in the tunnels under London as they route trains through the stations of the city – became controversial last week... but not for the reason I would have expected.

On Thursday, the BBC reported that "Tube drivers caught video-recording their journey and posting them on the internet could face disciplinary action" – and so my immediate thought was that this was because the videos would compromise Tube security.
In other words, wannabe terrorists would simply study these and other such videos in order to find points of vulnerability in London's infrastructure: soft spots, weaknesses, CCTV-free zones.
But no: apparently the real worry is that the drivers aren't paying attention. As one commuter explained to the BBC: "I'll wait for the next [train] because I feel the driver isn't focused and not doing what he should be doing."
After all, instead of paying attention to sudden and inexplicable deviations in the tracks ahead, the driver's too busy constructing a new subterranean Hollywood-on-Thames, cinematically mobile in the curved underworld of greater London.

(BBC story – and YouTube links – spotted on Metafilter. Earlier on BLDGBLOG: London Topological).