It's her choice if she wants to ride there or not, and she has just as much right to be on the road as anyone else. She doesn't have to be training for something to justify riding there. 500 feet in 1/2 mile sounds like a great ride and workout to me (in fact that's just the hill that leaves my neighborhood)! I never slow down or stop to let someone pass me. Why? Do cars ever do that for you on the chance you're stuck behind them? Getting as far to the right is the polite thing to do IF you feel it's safe enough, but its not always a viable option. Especially going down hills, you SHOULD WANT to take up the lane so that people don't try to pass you while you're maneuvering and then have you crash and also get hit by a car. Also, the shoulder is often where you find tons of debris and potholes. Keep in mind that your idea of a good time on the bike, is not everyone elses'.