There was research performed by the DfT on driver's perception of cyclists.
Using images of cyclists which were children, women and other images they showed that if the drive deemed a cyclist as "competent" then they would be able to cope with close passes and there was no need to slow down or move out when passing them!
It's no win - proper lights and HiViz and the muppets will drive closer!
Just before I read that post I found myself imagining 2 scenarios:
1) ''Ah, a cyclist in hi-viz, plenty of lights, cycling in a straight line, he looks like a sensible chap, I don't need to worry about him, I wonder what else there is to look out for...?''
2) ''Lordy, look at that cyclist with no lights weaving around in the gutter with a hood up and talking on his mobile phone - I better give him a wide margin, there's no knowing what he might do next...''
In the first, the cyclist takes responsibility and the driver doesn't, in the second, the cyclist doesn't but the driver does. I've no real idea if, or evidence that, such things happen in real life, but I fear there's more than a grain of truth to it.
Not an argument for going ninja, though. More an argument for getting drivers to take as much responsibility for cyclists' safety as a responsible cyclist does for himself.