Effective from whose point of view? There's a lot to be said from a fresh perspective on things, especially when it comes to identifying potential problems. I've done a lot of interviews with engineers and worked in industry myself and when you're within the box you don't tend to be able to carry out the necessary reflection very well, if you even think about doing it at all :)

Of course it does help to understand what's going on in a company to be internally effective, and it might take a while before an external person is accepted (as always), but in order to identify potentially negative social and ethical impact it can really help to have someone who is open minded and not tied to the particular traditions of the group.