I have only skimmed the thread but thought I would share some of my experiences as a cyclist in the UK.
I used to cycle to work (now work from home). There was one traffic light junction where the only safe option was to go to the front in front of the solid white line. That was because thre were two lanes of traffic sitting at the lights, the left hand lane of which could turn left (understandably) or go through the lights and turn left straight afterwards into a sort-of diagonal street, or go straight ahead. So, if you, the cyclist, wanted yourself to go into the diagonal street, there was no safe lane to be in - 'cos the majority of cars turned full left and didn't realise that you were going straight ahead and then left - but you couldn't go into the rght hand lane, 'cos some of the cars, quite legitimately, were going full straight haead - and you would cut them up.
I now regualrly cycle ds to school and then back home again. The number of times I get home ranting about drivers (on a route of less than a mile) that have driven dangerously in my path, where I have had to take avoiding action. Even though I would have been in the right, I would have been the one injured.
Every second or third trip a car pulls out across me (I am on the main road, have right of way - and there is even a lollipop man there) so that I have to do an emergency stop on numerous occasions. I am always wearing a high visibility jacket and (when the mornings were dimmer) have my front light on. If I could guarantee that I wouldn't be injured myslef, I wouldn't bother braking and would go into the driver's or passenger door and damage their car (that's how close they are when they pull out).
Drivers in thic country just don't see cyclists.
Picking ds up, we have to cycle up a short piece of road (100m max) where we position ourselves in the middle of the road as we are going to turn right, but also where there are often cars double parked on the left so that lazy drivers can "pop" into the Spar. The number of cars that are so impatient that they overtake us (cos they can't undertake us 'cos of the double parked cars) on this short section - on the wrong side of the road and directly in our path if we have started turning right (having seen that it is safe for us to do so as there is no oncoming traffic).
I always wear a helmet (especially since my mum sustained a head injury falling off her bike - even with her helmet on - but you can see where the helmet compressed as it absorbed some of the impact. That and her pelvis which she bounced on first) - but there is research that shows that some car drivers drive closer and more dangerously in the vicinty of cyclists with helmets as there seen as more "invulnerable" - despite the fact that helmets on really protect cyclists from their own falls, not impact from other vehicles.
Rant over 