The War on Britain's Roads (BBC Documentary / tabloid tv)

The black area around the Keltbay lorry is not the blind spot. That is the area which a driver MUST be able to see in the mirrors of a lorry registered after 2006. Older lorries that don't have to have the forward facing mirror will only show the area to the left of the lorry.
The real blind spot is the area further to the left, say 1.8 to 4 metres out where a driver can't see a thing. That's where people often get hit. There is a serious problem with the false view of the blindspot. I would say that any cyclist hit in the area shown in black (~= ASL) should have been seen by the driver. The crap propaganda from TfL has re-inforced some of the confusion over this. Prosecutors and courts fail to understand the rules and often tend to blame the cyclists.

Why did the LCC have this on their card, indicating a "lorry risk zone"?

picture is slightly different as the lorry is yellow and there's a subtitle under it that said "avoid the front-left of lorries near junctions".