[mikesears]

Originally posted by Bob M.
REPLY: While it's great to be able to evaluate yourselves from film, it typically isn't recorded for that purpose and you find that much of what you and your crew do--or fail to do--isn't even captured. We have two of our local members who currently work in the NFL. They often share their training films with us. It's not unusual to have an entire film devoted to "holding" or "OPI" or "late hits." These films are real game action with great clarity that point out the good, the bad, and the ugly with the supervisor's voice-over. You can learn an awful lot from that type of thing.

I totally agree.
Teams aren't concerned with what goes on during dead ball periods so they typically shut the camera off at those times.