I'm slogging through 3000 images of an event from two weeks ago.. (I SO can't imagine doing this without Photo Mechanic!!) The good news is that all 3000 shots are of beautiful dancers.
My workflow is to select a group of shots from the contact sheet, basically all the images from one setup, usually 20 or 30 frames. Then hit CMD+R and create a preview session. Works like a champ. Then I go through and crop and set ratings, and hit D to drop frames from the selection. When I'm done, I select the next 20-30 frames.
One minor problemo, which I consider a bug, is that when I set the rating on the last photo, the "Wrap around" kicks in and positions me back to the first photo of my selection. If I'm not paying attention, I could make a mess here.
My Wrap around flag in Preferences/Preview is unchecked, and all three "automatically advance" flags are checked.
Now I have to go back to work! Only 2800 images left to do!