I used to work opposite the Mercure Hotel on Southwark Street, SE1. If I had a pound for every cyclist I saw taken out by a Hackney Cab driver outside that hotel, I'd have several pounds.
Mainly it happened thus: punter would come out of the hotel doors, walk to the edge of the pavement and flag a cab. Said cab would swing into the curb without bothering to check their nearside mirror. This would be followed by a metallic thump and smash.
Occasionally it would happen thus: punter would flag down cab, cabbie would swing into the curb without checking mirrors, thankfully no cyclists would be present. Punter would then ask cabbie to take him somewhere in the City, across London Bridge. Punter would board cab, cab would swing a U-turn without bothering to check his offside mirror, as a cyclist was overtaking him. This would be followed by a metallic thump and a smash.
Once or twice, the cabbie concerned proffered a SMIDSY. All the other times, the cabbie would harangue the cyclist for his or her stupidity, what with him being a professional driver and all that, and therefore infallible.
I don't bother taking cabs in London, partly for the above reasons.
I'm more than happy to take cabs in Liverpool, however, as the cabbies there are boss.