This is obviously true - you pass through the same amount of water horizontally on the way to your destination, but there's less time for it to fall on you vert

This is obviously true - you pass through the same amount of water horizontally on the way to your destination, but there's less time for it to fall on you vertically. However, the main problem with running in the rain if you're not careful is that you will spray yourself with water from your shoes. That may or may not get you wetter, but it could also get your clothes dirty. I aim for a short of shuffle-jog. :P