I agree with my colleague.
From what I've seen when I've looked at work that consultants have done—on appeal, for example—it tends to reinforce the horror stories, as you say.
The problem is that consultants are limited in what they can do. They can put forward an application but they can't represent someone in court. The lack of training and the very narrow scope sometimes prevent them from seeing what can happen with an application down the road if there's a problem or if it needs to be appealed. Unfortunately, a lot of the things that determine what is going to happen down the road are things that are done at the very beginning. If you don't get it right at the beginning, you're really limiting how you can fix it later on.