You are correct with #2. The rider coach in the BRC class did a great demo on that. He had me be part of the demo. He had me sit on the bike, adjust the mirrors to where I’d set them. Then he stood in my blind spot, and asked me to see if I could see him in my mirrors. I told him I couldn’t. He slapped the side of the bike. The point is, unless your head is turned around all the way to your shoulder, you can’t check your blind spot. And unlike in a car where swapping some paint involves both of you exchanging insurance info, going on with your day, and a trip to the body shop in the next few days, having that happen on a motorcycle involves you getting hurt and your bike getting messed up.