I feel by informing the client about he over dig is being honest and upfront as opposed to not telling them. For the contractor that knows better and doesnt bring it to light. Aka get in and get out -They won't have settling for a few years. Unfortunately there are contractors at will not go back when they get he call about settlement. As I stated earlier this method doesn't only apply to new construction. What about the 10 year old house that is having the deck replaced with hardscape? Your right it's on a case by case basis. Most of the time people don't want to wait a few years. This is the best option if they have to have it now. The cost should be relative to the size of the project. It could be just steps or a full blown raised patio. At the end of be day customer needs to be educated and well informed to make the best decision. With that being said some could care less and go with the CHEAPEST price. This method should be an industry standard in my opinion. I hope you include in your Hardscape University.