It's a get-out-of-jail card. If a cyclist is injured on the near-side of the door, all the driver has to do is blame the cyclist and nothing happens. I treat vehicles with those signs even more carefully, they've already gone to the trouble of getting an alibi ready. I just had a white Audi deliberately swerve at me coming the OTHER way, he jerked his wheel over. Lots of drivers hate cyclists, I imagine they'd be keen on signs like that. They have signs for speeding on my commute too. More safety on the roads! They're busy signs, they flash the numerals "30". I see them both flash every day, going and coming home. Tremendously busy little signs working away all day, flashing, making things safer on the roads.
1. I'm not sure it would work as a 'get out of jail' card. It may be that a filtering cyclist is found to be at fault in a collision, but I do not believe a sticker on the rear of the other vehicle would sway our judiciary.
2. I really don't think those signs are there as a sort of
at-the-ready alibi. There are vehicles I think twice about filtering inside and vehicles I think three times about. I do ride with extra caution around some vehicle types, but not because they've put a sticker on their rear panel. Why would one suddenly become suspicious of the motives of a driver displaying that sign?
3. Do drivers really hate cyclists? In forty years of riding in several countries, no-one has taken a swing at me with their vehicle.
If one really believed that lots of drivers hate cyclists (as suggested above) enough to swerve at them on the highway, I think it might be time to stop riding and leave it to those of us who love the roads and get on with other road users.
Neither as a driver nor as a cyclist, have I ever felt that another road user might hate me or wish me ill. As a former motorcycle courier, you'd imagine I'd have picked up at least a little of the hate that was out there.