From Mike M...
>I wonder if Hockey East is the only conference that stipulates that
>goals shall be called by referees and assists by SIDs.  It is
>certainly to be expected that when the home SID is calling the
>assists, he will know his team better than the opponent and may
>inadvertently award more assists to the home team.  What counters this
>is that the visiting SID is almost always present, and you tend to
>defer to the visiting SID in scoring matters concerning their team
>unless there is a conflict - then home SID makes the call.
 
I'm not positive about the current situation, but I believe Michigan used to
employ a "caller" and "writer" in the press box.  One person would call out
the number of the player with the puck and yell "switch" for a change of
possession.  The second person writes everything down.  This can be helpful
in determining assists.
 
 
  John H
  U Mich