I load 45 ACP, 38 Super, and 9mm on my Dillon presses, with carbide dies, without lube, and always tumble first. Whether you use corncob media or walnut hulls, I don't think you're going to get any appreciable amount of cleaning done in the primer pocket by tumbling after decapping. When I load rifle ammo, of course I have to use lube, so I tumble first, lube, size, then tumble again to get the lube off. Then I have to inspect each case for media in the flash hole.