Having conducted a recent survey of my travels it does appear that cyclists in the UK suffer with extreme colour blindness, in particular at junction where traffic lights are present.
The inability to distinguish between red and green appears to be the most prevelant, and also determining when a light is at the top or the bottom of a traffic light sequence.
I find it a continuous source of amusement that a cyclist will bomb straight through a red light in the vain hope that the number 7 double decker won't be hacking through their green light at the same time.
Other road signage cyclists seem to have visual problems or intellectual misunderstanding with include:-
No entry signs....apparently this is only for powered vehicles.
Zebra Crossings...cyclists always have right of way over pedestrians apparently.
Pelican Crossings...colour blindness kicks in here, and red definitely gets confused with green.
Pavements...even if not designated as a pedestrian/cycle path these do appear to be for the exclusive use of cyclists.
Cambridge and Oxford (understandably) appear to be the hardest hit, with a varying array of skill and talent to misinterperete every road signage.
My suggestions, lets get back to proper policing, on the spot fines for these morons! Let's bring in a license plate scheme for bicycles and cycling licenses so there is some goddam accountability for these muppets!