This has probably come up before but do you think it is taught or necessary to look over your shoulder to check blindspot when changing lanes on the motorway?
I just need to add an edit. I’m specifically referring to looking over your shoulder on a motorway. Checking mirrors and blindspot is not under question
It’s easier with more modern cars, because you can see the lights on a side mirror light up.
In general if you are less than a car length behind someone, until you can see them is not a great place to be.