Certainly one can attempt to hand-hold below the typical
camera-shake threshhold (1/n shutter where n= focal length),
but IS really does help--even at wide angle. This image
is not presented as perfect, but merely an example of one
kind of scene you can easily shoot with assistance from IS.
In this case, a "fast" lens (wider aperture) would be problematic,
since you'd lose depth of field...so IS is a real help in
situations where you can't use a tripod, yet need to maintain DOF.