Tom seems to think you don't really get erosion there. I think otherwise. Other than your water is way colder , for the most part targets probably don't move around much , hence the "Goldfish bowl effect ". I would also think the very low or minus tides are the only time to truly be successful.
We get plenty of erosion here.. we don't get huge cuts like the west coast gets but we also don't have beach replenishment done here.. Our rocky beaches will erode... with sea levels rising more gold that is stuck deep in the slopes will be freed... after superstorm Sandy rolled through here I killed it the gold was covered in green telling me it came from the wet sand..
When Tom posts those long replies... I don't bother reading them.. if you can't get to the point in a few words its all a waste of my time.