I think you're seriously underestimating kids and beginners! I live on a steep hill, the kids who play on it range from about 3 or 4 to about 10. All of them are fine going up and down the hill, they actually get up to a decent speed. Even when they do fall off, it's a few tears and all is well - it's a part of growing up/riding a bike.
What do you want? A totally flat course covered in pillows incase someone falls off? Anyone who can't handle the linked course needs to take a serious look at themselves! Besides which, why are you worrying on behalf of anyone else? Can you manage the course? If so, where is the problem?