And why the f*ck must downhillers always yield. If there is enough space, just smile and wave. On the contrary, there is a perception in SA the uphill has right of way. Piss right off... I have often passed people when going downhill and they have their heads up their poepols and do not pay attention, and then it's the descending guys fault when they get a fright. Learn how to ride and get out of the way. I will however slow down for walkers and especially for dog walkers, and will usually give a cheery greeting and a big grin.
