To be honest, I never use my right arm to open the left door, and I never heard of this practise. But I will always look in the mirror or behind me to check if

To be honest, I never use my right arm to open the left door, and I never heard of this practise. But I will always look in the mirror or behind me to check if a bike or scooter comes up from behind. In big cities like Utrecht and Amsterdam, in certain neighbourhoods with lots of migrants, it is - as a cyclist - not safe to assume that someone will check for cyclists from behind. You - as cyclist - have to take care of yourself, which means driving more on the road instead of the cycle path. As an experience big-city-cyclist this is no problem for me. I merge with car traffic without thinking. But I see it happen all too often that cars take a left or right turn without looking back. Same with people crossing roads without looking left or right. They just assume that the other people will stop. These are mostly migrants not used to our way of doing this, but more and more people using their smartphone in traffic do exactly the same.