My father is red-green color blind. My mother first learned of it when she asked for a pair of red jeans for Christmas one year (back in the 80's ). My dad went shopping alone that year and when she opened up her green jeans on Christmas morning, she told him 'never again'. From that year on, my dad was only allowed to buy clothing for my mom if I was around (or if she'd already picked it out!).

And yes, he sees traffic lights as top/middle/bottom. He had to do some adjusting when he moved to FL and discovered that many of them were hung horizontally!