I gotta disagree with the mirrors comparison. Way back when I took drivers ed, I was instructed that we could use the mirrors, but we are required to turn our head and look backwards before changing lanes. Mirrors are good, but drivers still need to actually look.
Your instructor wasn't too good. He/she should have shown you how to adjust your mirrors to avoid blind spots.
You actually turn your head around and look behind you before changing lanes when driving? I find that hard to believe.