You should never be looking behind you while you are moving forward. Its just common sense (tho a lot of people lack it). Back up cameras have ruined people. I remember when I first started driving, figuring out how to use your mirrors took some time to kind of wire your brain to use them properly. Take some time to setup the mirrors properly, then to check your blind spot you just lean forward to sweep through your mirrors view. Its not difficult and its much safer than turning your entire head.