I can say I have helped several people with this problem that never posted to this forum ...
It is an issue, period ... now we can debate if it's a mount problem or SGP ...
I would just like to see an option in SGP to do just a slew without sync, in software like carte du ciel you manually need to add a sync point after you confirm, SGP should enable such a workflow, slew and sync, or just slew ...
Now what I do is to instruct eqmod to only add manually points, but that is a workaround ... and if your mount has no such option you are really depending on how well the formula can cope with lots of points some pixels away ...
/Yves