George
I borrow the term "yard trashing" from a beekeeper friend who has never
used the method but who read about it in a bee journal article a few
years back.  I have not read the article nor talked to the originators of
the method but have used our version of it with success.
Basically: We have all mediums.  From fall to spring our brrod nests are
three mediums with an excluder above.  The hives are palletized but the
method would work--though involve a little more labor--without
palletization.  In mid-March in central Texas at 33 degrees north
latitude, we perform a three-way split on each hive.  This involves
rotating each pallet in place 90 degrees so that each north hive now
faces east, east--south, etc.  An empty pallet is placed on each side of
that pallet with identical orientation.  The orginal hives are then split
onto the two empty pallets turning four, three medium hives into 12, one
med. hives.
 
Of course, this assumes no empty slot which there are.  You just use what
empty pallets you need to make all the splits in the yard.
 
You do not touch a frame or look for a queen.  A ripe queen cell is
placed in each hive and feed is given if no flow available.  come back in
15 days and check for queen right.
 
Three men make turn 40 hives in 110-120 in less than an hour.
 
Clint