I believe I am paid as a consultant to bring my expertise and experience to the client's situation. I do get input from the client and staff but don't know how much involvement is enough. At some point, I am just educating staff, and that is not what the client is paying me for.
You are looking at this situation the right way - using staff as needed for valid diagnostics but not spending time on non-value added (per your scope of services) activities. However, let's consider another aspect of the engagement. If you are exceptionally cost-efficient in diagnosis and solution design but lose momentum or fail in implementation, then this was all for naught.
In almost every case, clients need to be part of the solution (sometimes diagnosis as well) to be enthused and supportive of solution implementation. Take the now-famous example of Edward Bernays, who used the psychological research of Freud (his uncle, by the way) to change some fundamental aspects of marketing and influence and coined the term "public relations." The point was not to appeal to reason but to the subconscious feelings of the buyer (e.g., using sex to sell cars).
The story goes that Bernays realized that women in the 1940s were not buying cake mixes because they felt ashamed to give it to their husbands because they were doing so little work. Bernays advised Betty Crocker that changing the formula to require the addition of a fresh egg would change the way women felt about this. The strategy worked. Women felt they had done enough to deserve praise for their baking and the cake mix sales skyrocketed, a process we see today, even though the original conditions no longer exist. (More detailed videos of this effect
For the reason people who assemble their own furniture are so loyal to the IKEA brand, your clients will accept and embrace your work if they are given an active part in its development.© 2010 Institute of Management Consultants USA