The fatwa aside, this is a nice idea but I wonder if it's enough. What if meetings are shorter but just as ineffective? People generally have no idea how they are being perceived by others, which is one reason that videotaped job interview practice can be effective. Feedback on meetings needs to be part of a meeting.

My wife has a manager who mumbles for two hours and still doesn't cover the agenda. He's defensive and squashes dissent. His problems are more than meeting skills but neutral feedback on his meetings would be a good start. Two hours?--most people stop focusing after around 45 minutes at the most.

Ideas: a meeting cop--someone from another department not involved in the actual agenda--sits through the meeting and gives 5 minutes of (private) feedback?

Audience feedback, indicating when the meeting convener has overstayed his welcome. Something visual, like turning a cup upside down. When all the cups are upside down, you've blown it.