I've taken just the drum off before. I had just done the hub with new seals and all that. I sealed the crap out of the keyway too, and I did not want to redo it. The brake shoe return spring broke and I had to get in there. Replaced the wheel cylinder too cause it got all ate up from the scrap being tossed around.
I drilled a 3/8 hole in the back of the cover and used a flat punch to smack the drum loose as I rotated the wheel. It was all painted to the hub, but it did come off. I have singles, so it wasnt a big deal to take the wheel off. You have to place the hole very accurately, right on the perimeter of the drum.
Probably takes the same amount of time, hub off or that way, but I was just being stubborn. Plus, you dont get all greasy and have to worry about keeping everything perfectly clean.