In the '70s, I ran into a field supervisor, associate director of a
     major archaeological contracting operation, who still followed the
     procedure of trenching along walls to outline a historical structure.
     This was in the same period when prehistorians of this operation spoke
     proudly of how large a number of cubic meters of earth they removed
     from their test units in a day.  Apparently the concept of "maximum
     information for minimum earth removed" had never occurred to them.
     Turn of the (previous) century methods are still with us.
 
     Jake