Thanks for the clarification.
I have a couple of questions related to the topic of AF:
1) When your lens is on manual and you select the 4-point or 9-point "expansion" AF modes, does the focus confirmation dot only care about the center point of the 4/9-points, or will it actually evaluate the surrounding expansion points? And what about if you're in "Zone" AF mode? I ask this because the Canon manual made a specific case about the 61-point auto selection (i.e. that the focus confirmation dot will only be evaluating the center point) and didn't talk too much about the two expansion modes or the Zone mode. Just to clarify, I would never consider actually being in any of these modes when my lens is on manual (I'd just stick to Single Point AF), I'm just curious what the system would actually do.
2) A related question I had was regarding AF during Live View.
Does being in x1 vs x5 vs x10 magnification affect Live View's contrast-detect AF system at all? In other words, does engaging the AF while in x10 have different behavior than engaging the AF while in x5 or x1? (Perhaps more precise AF while in x10?)
One of the reasons I ask this question is because on the 5D Mark III, the AF box on the rear LCD screen actually changes size when I change the magnification. I think the x5 and x10 AF box is the same size relative to the screen's size, but the x1 AF box is different. The practical effect is that when I'm shooting, say, a focus chart on the wall, when I'm in x1 the AF box is surrounds the chart. As I zoom in to x5 and x10, the AF box size changes and is now "inside" the chart. Basically, the region of space that falls under the LV AF box changes between the three zooms, so I'm not sure if the AF is changing along with it or if it has no bearing at all and only affects what the user is seeing on the LCD.