Having trained in the Schweizer I can confirm that, at hover taxy speeds, the dutch roll this machine can experience can be quite severe. Back in my student days I almost called the tower to say I was unable to control the aircraft!
Part of the problem is that students are told to always taxy with their skids in the direction of travel (obviously sensible for engine failures, inadvertent ground contact etc). A long hovertaxy along a runway with the wind from the wrong direction can be an unpleasant experience as the dutch roll builds and the student chases the controls to no avail.
Put the machine out of balance thus changing the angle the wind hits the aircraft and the dutch roll disappears almost instantly.
As I got more proficient I'd sometimes set it up so I could see if I could control it. I never could, but then again I couldn't hover within 5 minutes.
