So am i the only one who uses a different technique? I always look in the side mirror (the one on the driver side=left side) before i open the door, where i can perfectly see incoming bikes/etc passing my car. When i got my drivers license i was taught to do this and it became a habit, so i've been doing it ever since. Works very well.

fyi i'm Dutch and i've never heard of the "Dutch reach" before.