Here's a link to a PDF of one of the MPSC newsletters they send out a few times a year. If you scroll to the second page, it contains an article from the DOC about being "silent" during games.

http://www.mpsoccer.com/images/homepage/MPSC-Fall06.pdf

Courage is what it takes to stand up and speak; [it] is also what it takes to sit down and listen.