"Having worked with a number of these "consultants", they are often only 1 or 2 steps ahead of the technical staff at their clients"
I see that you've been lucky, most of the consultants we get from the body shops we use are usually at, or below, our level. Its just that the consultants have fancy certifications while we, the in-house folk, do not (Because management spends way too much on consultants, leaving no money for training). At least this has been our experience with Accenture, Crapita, and PWC. Even worse was when management decided to go lowest bidder and brought in Tata and Wipro.