As part of my insights into the consulting process, I realized that the report is not the product of a consulting assignment but part of the change process. Remember people only do what they are ready to do, even consultants. On difficult assignments we often want to produce the report, get sign off and get out of there.
Often the readiness for change is low and you know nothing will change. I have found even in those situations a worthwhile step in the process is to engage the clients key people in a dialogue about the content in the report. The approach I often used was the stamp the report "Draft for Discussion Purposes Only". Then I would invite comments, edits, and discussion. It was a great consulting tecnique for assessing readiness. Another technique was to give the report a version number. That also implies that you are open for changes and suggestions.
Another similar technique is to call the report "An Agenda for Action." All these ideas are to recognize that the product of a consulting engagement is change. The measure of success is the degree of positive change. We are not hired to reveal the truth but to improve the situation.