Role of actors in design?

To piggyback on Jenny's question/comment from an earlier post- what about the role of the actor in the development of the design?

When the text itself is experimental or develops organically in the production process, how does that effect the role of the actor in the development and execution of the design?

This is always a sticky spot between actor and designer- how many of us have heard "This isn't what I thought I would be wearing..." or "I don't think I would wear these pants..." and other more direct refusals of designs. But what happens in a situation where the actor is author? How does this effect not just process, but the sharing of "creative license" as well?