maybe he had a big mug and had to turn it over... (sorry, it's happy hour here)
i add sand slowly, say three or four days to add a bag to bolster my DSB. i turn off the pumps, and add it like uscharalph does. i've got pretty strong flow in my tank, and fresh sand goes everywhere, it needs a little time to get gooked up with bacteria and stuff and settle itself down. this is my main reason for doing it slowly.
i also run a cannister filter with carbon off my sump while doing this, it helps clear the water and it's something i like to do for a week every now and then anyways.