Thanks for the responses.
I have done 20 minute exposures with no noticeable rotation since using
this technique. But I haven't been as active in the last few months.
I will play with the 100% and 150% corrections to gather "empirical"
data. But, when I get out, I get lazy and just do what seems to work
and get the eye glued onto the eyepiece as soon as possible.
What I have noticed is that when using this technique, for a several
hour observing session, dialing in objects with the DGC is pretty
awesomely accurate. I get disappointed if the object is more than 25%
away from the center of a medium power lens. ;-)
Thanks for your inputs, again!!