What is this bread making technique called?
The "well method" is commonly used in pasta making, though some bread bakers also use it. When one uses an autolyse step in bread making, all the flour is mixed with water.  This begins hydration and enzymatic processes.  With the method you describe, all of the flour making up the "well" is just sitting there...inert.  The only thing I can think of is that the baker in the video is letting the yeast proof before mixing.