I remove the foil shield then I twist the drains together (from all the cables) then wrap that around all the cables , then tape them to insulate them. I make a habit of this regardless if the drain is being used or not. This way when the drain is being used it is second nature to do so. I never cut them off .The other electrician most likely has never dealt with or was not taught about shielded cable. The best thing to do when faced with a question is to do what your doing, ASK IT , and Research it.