Rapid deflections of ground signals due to, say, other aircraft interfering with the signals, are recognised as such (and the aircraft doesn't go crazy trying to follow the signals).
Interesting point. Apparently that didn't work out all that well for the
777 from singapore airlines in munich a while back. We tried the same in the 737 simulator and the results were similar, even more annoying was the fact that we could not disconnect the autopilot by overpowering the rudder, that worked only on the yoke or via the normal disconnect buttons. As it is the most intuitive way to disconnect we actually managed to overpower the simulators hydraulics by kicking into the rudder.