Ben - take a meter reading off a gray card at the location of the subject with a reflected meter. Take another reading with an incident meter, aimed properly (in the position of the subject, pointing at the camera, held vertically, etc etc). They'd better darned well agree! That's what they're supposed to do! As I said in my longer spiel that you quoted, an incident reading will not take into account the overall tonality of the scene or what you want to do with that - using the reading from an incident meter will place the tones of the scene where they ARE, not where you want them to be. You can interpret that with a reflected meter, by reading the subject brightness range, and then setting the meter to render what you want middle gray to be, or you can skip a step and just meter the thing you want to be middle gray, and set the camera accordingly.