For instance, I live in Wimbledon and often visit Teddington. I used to always use the route the satnav told me to, until our friends who live there told us of a different way of going which took about half the time.
Their route still used main roads - it wasn't some back street short cut. I know that routing is a complex thing, but this seemed so obviously wrong. Does anyone else have this problem?
I also wish I could train my Tomtom to remeber the better route so it chose that one in future.