What is it about my previous statement that you don't understand? Let me repeat, his marginal tax rate on both ordinary income and Schedule E income are identical. If they were not, why in the world do you think he is doing this? The pure pleasure of paying more tax?
I don't know about the tax treatment... it has been too long since I studied tax law. I can, however, suggest another reason "why in the world" Edwards would set up his practice as a corporation. It's a liability issue; for example, if he is sued for malpractice, then it can (I think) protect some of his personal assets. There is, of course, something called "piercing the corporate veil" to get at personal assets, but it can be an uphill battle as I understand it. Oftentimes a corporation is set up for liability issues as much as tax ones.