You can ask Madam Raven a question by dropping an email to firstname.lastname@example.org and she is also now in the land of Tweets, check out @MdmRaven and ask her any cycling question you dare.
* * *
Which colour do you think is best for being seen on a bike?
I have an untested theory that the most visible outfit would be one that matches exactly that worn by traffic police officers: a yellow just this side of radioactive sunshine with fetching decoration in chequered Scotchlite and reflective blue, including the word "POLICE" emblazoned in large, black letters.
The average motorist being, in my experience, less than habitually law-abiding, has an instinctive reaction to a police uniform. I do not believe there is any conscious brain involvement. The sight of a uniform causes an immediate tap on the brakes with an attendant glance at the speedometer, particularly in urban areas, and a marked increase in the level of courtesy. I suspect the standard black and white uniform would also work. Unfortunately both of these options are illegal, unless one happens to be a bicycling police officer.
If other road users are looking for cyclists, the colour is largely irrelevant as long as it does not blend in to the background. The number of drivers complaining about cyclists wearing colours other than cornea-searing yellow or orange is paradoxical proof that the cyclists have nevertheless been seen. Urban camouflage and cloaks of invisibility are to be avoided.
Hi-viz is popular, however the number of cyclists suffering SMIDSYs while wearing it suggests that it is no guarantee. Visibility is a popular topic for discussion on many a cycling forum, and it would seem that the majority of cyclists agree that road positioning is the most important factor. The "what the blazes?!" effect is also very useful, as evident in the effect on drivers of riding a recumbent or attaching a trailer decorated to look like a whale in an 80s-night roller-disco costume.