So I usually compromise by keeping a small sliver of the car visible in the mirrors and turning my head at least slightly when I use them. I think that's probably the way to optimize for real-world safety.
Another pet peeve is a feature my own car has, which is an auto-dimming function that's intended to cut down on glare from nearby headlights. If I turn that on, the side mirrors get so dark that I can't see cars that don't have their headlights on, which is all too common near dusk around here. Extremely dangerous implementation of an otherwise helpful feature. One of these days I'm going to open up the mirror housings and clip the appropriate wires, since I really only want the interior mirror to adjust itself.
Let me share a story. I am blind to my left eye which means I have to turn my entire head way, way to the left to be able to look into "blind spot". Once I almost crashed the car when looking into "blind spot" when joining into busy highway because the car before me broke hard as some other care before run out of space. Only my wife screamed and I instinctively slammed the brakes and stopped few inches from the car before me.
This was about 10 years ago. I started reading about how to fix this problem and I found the article why and exact procedure.
It took some time to get adjusted. Particularly, driving with no traffic at the beginning meant there was nothing in the side mirrors which was disconcerting. Also, when you back up with your car you have to tilt to be able to see the side of your car. But, remember, you can back up as slowly as you want but when you need to join moving traffic you have to do it at speed.
Nevertheless, I finally feel free in my car. I know exactly what is happening around me just by scanning the mirrors with very little head movement and on the lanes directly to the left and to the right I have no blind spot where a cyclist could fit. There are blind spots on further lanes so if I change lane I still need to make sure there is no car that decided, at the same instant, to also change his lane.
If you sit straight and you see the sides of your car even a tiny bit then your mirrors are way from being well set up. It is not a compromise, you have a huge blind spot unless you have particularly large side mirrors. Thats because your rear view mirror is a cone, and the job of your side mirror is point exactly in the middle between your peripheral vision and the cone shown by rear view mirror. If your side mirror sees the side of your car then over half of your rear view mirror is duplicated with your side mirror. If both side mirrors are set this way then you don't really need the rear view mirror as in both side mirrors you see the road behind your car.
For me this is mostly about the extra time it keeps me from making a stupid deadly mistakes. Switching lanes that way takes longer, and this is a feature not a bug.
