I would say the reduction in cycling is a pretty significant effect. I love cycling, but I am far too scared (or wise) to ever consider riding on a street shared with cars and trucks. In the end if anything goes wrong the driver will feel sad and I won't feel anything.
I've been cycling in traffic for almost 3 years in a country with no bike lanes and pretty bad motorist behavior regarding cyclists. It was scary the first month, but then you get used to it and you learn a couple of rules that reduce your chances of getting into an accident significantly [1]
Learning these rules really makes all the difference. Would you prefer to get into an accident and not get killed (thanks to a helmet), or to significantly reduce your chances of getting into an accidents altogether?
A note on gear: get all the lights (front, back, laser lane) and reflectors (for individual spokes and tires too) that you can, set them up to blink, and use a bell and a mirror
Please keep the blinking reasonable and non-distracting. A lot of cyclists where I am have what amount to high-powered strobe lights aimed at car-driver's faces. I've also been the victim of this while riding my bike down canal paths at night. It's no fun being completely blinded while a fellow cyclist zooms past.
I'd be so annoyed by the helmet, it messes up my hair, makes my head sweaty, I have to put it somewhere or keep it with me the whole time. It would really make me bike less. Then again I hardly ever have to share the street with cars and trucks and if I do it is with a lot of other bikers. This is not at all uncommon during rush hour: http://www.youtube.com/watch?v=n-AbPav5E5M
It is so great that video looks completely normal to me. Dutch cities and towns are full of bikes. It's the best way of transportation. Clean and healthy. I have no car, just a bike and I always take public transport or bike. Sometimes I'll rent a car. Rain and wind are rarely an issue. I can recommend anyone to aim to live in place where biking is safe and easy. It adds daily fun to your life.
> In the end if anything goes wrong the driver will feel sad and I won't feel anything.
This is pure hyperbole. As someone who has been hit by 6 cars, most accidents are minor. Sure you will end up worse off, but only a couple have I not been able to ride away from, and that was because my wheel was damaged.
Of course, I started to wear a helmet after about the 3rd time.
It is not really hyperbole when it come to the consequence of a serious accident. Hundreds of cyclists are killed every year by cars and trucks, but I am yet to hear of even one driver killed by a cyclist - this would be a man bites dog type story.
You are far less worried about risk than me - if I had been hit 6 times by cars while on a bike I would not even be able to look at a bike without feeling ill let alone ride one.
