I've observed exactly this sort of sun-in-the-eyes behavior, and -- confession time here -- probably done it a time or two. You're in your car, you're stopped...and you realize that with the angle of the sun, you simply can't tell if the way is clear or not. What to do? It's one thing if you have a traffic light, in which case you could just wait for the green and be reasonably sure that there wouldn't be any cross traffic...but if you have a stop sign, you're kinda screwed. Low fall and spring sunlight is the cause of a lot of accidents on east-west roads -- I've been turning on my blinkie earlier these days in the hope that it will help me stand out against the glare as I ride west in the evening.