What to do with reports request that duplicate other reports?

Vincent, we are facing this situation right now because the initiative the organization I am working started time ago and I am leading. And your question helps me in clarifying my previous comment. The key here is value. All our actions are part of a framework intended for constant value delivering. Value, as you know, is a subjective matter that we need to translate into objective ones. And the driver to do that is organizational strategy. All the information we deliver is aligned to strategy. The format of the report has to be changed according to your audience. But the information is always consistent between reports. In fact, inside the whole initiative, we are making a great effort to put all the data in one place, to teach all stakeholders about how to convert the data into information.

Different audiences require different communication methods and artifacts. And as you would imagine, the breadth of variation is infinite.

I find it helpful to always ask the customer of the report specifically what action they intend to take when they finally get it. If they can't provide a clear answer, it may be necessary to help them think about what it is they are asking for and why.

Of course if the request is an arbitrary request from a person of organizational authority, generally the only option is to 'trade' the time it takes to do the additional work by eliminating something else.

A well defined Master Plan and Project Communication Plan should sort this out... We as PM should avoid information overload as much as we can