Adjusting side view mirrors

They can adjust them that way if they want, but I have always adjusted so that I can sight down the side of the truck. This works for me as I am often navigating both forward and backwards in tight environments. Both of my trucks have full size tow mirrors, that have a separate wide view convex mirror at the bottom, that is adjustable independent of the top portion glass. I have no blind spots on either side. I have that wide convex adjusted out far enough that I can literally still see the passing vehicle in that spot mirror as he is right along side me and I can see him in my peripheral vision.
I even use "stick on" wide view convex glasses on the edges of the mirrors on both my street motorcycles.
The best part of their little PSA there was they reminded people to look twice for motorcycles.