Pivot parameter for PolyExtrude SOP global transformation
Middle click drag works without any update for objects. Tricky part is that you have to have object you don't want to update selected before you do middle mouse drag in the timeline. So if you don't want to update whole scene, select all objects then MMB drag in timeline, you should see orange line from old frame to new frame. I think it was designed for keying same pose of selected object on different frames. For DOPs you can disable just simulations (dop networks) in menu or LMB clic
