I have no interest in racing, for me a bike is a mode of transport or a pleasant way to enjoy the countryside.
Currently, the only time I ever stand is to accelerate from stationary or for a very short, steep hill... I can't do it for more than about 30s and it ruins my legs!
Friends of mine say they never stand, us it something that's useful to practice or really only for racing? Does it perhaps use different muscles so can be used to alternate with sitting on a hilly route or something, or is it fundamentally a hard core skill?