What Foundation's CEOs think about evaluation

What Foundation's CEOs think about evaluation is the title of an interesting post in a new blog from the Chronicle of Philanthropy about a recent survey in this domain. A majority of CEOs claim to be in favor of evaluation work but the post does not say if they agree to make the results public. How many evaluation reports remain safely sealed and strictly kept out of reach for fear they would trigger unwanted changes or questions about how the Foundation operates?