It's not THAT stupid. Less than 20% of rapes are committed by strangers. Many thousands of men and women go door to door all over the country for a variety of reasons, and how many are dragged in and assaulted? It must not be that common, I couldn't even find a story about it.
The number one rape prevention strategy, going by the numbers, should be to be careful around your family and to watch who you make friends with!
True that.
However, I still think it's a stupid thing for a lone woman to be knocking on stranger's doors. Door to door isn't that common anymore. Not like it used to be anyway. Granted, the odds of that happening may be low, but if you're going to be advocating prevention, you need to demonstrate it a little better. All it takes it one wrong door. Simple solution? Go in groups.