Dry washing is an important tool to go with detecting. I've found plenty of little patches that give a dozen or more smaller nuggets in a limited area. Dry washing is a great way to clean out that patch and get all the gold in the area. The photo below is from a little patch about 5 x 30 feet in size. Nuggets on the right were detected when the patch was found, gold on the left of the coins was dry washed from the same spot after the nuggets got harder and harder to find. The dirt was only 6 to 10 inches deep at this spot. Detected gold was around 15 dwt, dry washed gold around 10 dwt. I've dry washed a few more dwt from this area since and detected a few more as well, but this was the heart of the area.
Interesting too on the original photos of the gold the guy got near Randsburg. I dry washed near there maybe 40 years ago. Its surprising how small the size of gold a dry washer will get. On the dust sized gold you are not getting 95% recovery but even of you are only getting 75% on the really small stuff, it still can add up to a lot of gold.