Coach Chass is absolutely right. There was a famous study done in the 1950s based on a particularly rough football game between Princeton and Dartmouth.

"After showing a film of the game, Princeton students �saw� the Dartmouth team make over twice as many rule violations as were seen by Dartmouth students. The researchers interpreted this as a manifestation of selective group perception. They interpreted these results overall as indicating that, when encountering a mix of occurrences as complex as a football game, we experience primarily those events that fulfill a familiar pattern and have a personal relevance to us."

Read more: http://www.experiment-resources.com/selective-group-perception.html#ixzz1Ijqru5k2

In other words as parents, coaches, players, and fans we are very unlikely to "see the same game" if we are aligned with opposite teams.