Possibly. But they should hod steady with SH.
The main thing is the Galil cannot hold them still if the encoders are not providing feedback. So the encoders working properly is crucial! And then the KP, KI, and KD Galil parameters need to be set as well. The last I saw in your debug output was that they were set at stock values.
So are the encoders working?
Go into the terminal and issue this:
DPA=0
SHA
This will set the encoder count to 0 for the motor on the Galil X axis and then activate the servo loop for that axis as well. What you should see is the encoder count at or near zero. If it is some wild out there value, then you don't have the encoders hooked up right.
Where are you located?
Steve