A 'runner' is a person who has that as a born ability or goes through a certain special event. They are awesome because they do everything at twice the speed except age and have children.

The only real benfit to putting 2x speed on is that everything goes faster. Unfortunately the villages also age twice as fast, so you're really just rushing things. Now I did have one time where I had hardly any food, so I put it on 2x until the garden grew. I don't know that it really made a difference or not to the villages though.

Marcey