As VH said, the NWS becomes very over-sensitive at higher speeds. My boss got tired of pulling his planes out of the weeds, so he banned us from using it for either T/O or landing. He also told us not to bother with the test procedure, because it always failed.
Even without the NWS trying to kill you, you can still wind up in the weeds. Not sure why the Metro is so hard to rig properly, but we frequently had large splits between power levers. Talking about "parallel power" is all very well, but the reality is you had to remember which plane you were in, and which power lever to lead with on both T/O and landing. When I found myself using full reverse on one side with the other side forward of flight idle, I considered it was due for a write-up.
a 737 classic sim feels like a metro
My deepest sympathies to all those 737 pilots!
Can't believe I'm the first one to mention that the entire NWS is MEL'able for 10 days. Did Fairchild not manage to sell that detail to any agencies outside the FAA?
Referring back to the OP, the sudden lurches would be either engaging the NWS with the rudder pedals cocked after a crosswind landing, or fighting with an improperly rigged aircraft.