Hi Bud,
I believe the question you are asking is, With all of the people that have the ability to get a good edge, how much metal are they sacrificing to get one? If that is the question,here is my answer.
If they are learning on their own and starting out, way too much. I say this not from arrogance but in learning that took me many years to accomplish. Lack of experience no matter what method you adopt always involves a sequence. Intervals require the sharpener, to understand what has happened at each step and that reqires feel. Professional Honers make money by knowing exactly when to stop at each step so they don't waste time or money or steel. Amatuers can learn this too, but until they develope a feel for what happens at each step, they are going to waste lots of metal.