I use a 5D and a 20D, and I always use them in AI-servo. I shoot from weddings to airshows. The unlit points have never even crossed my mind. Is there something about the cameras in question that makes this an issue on them where it's not on my 5D and 20D?
It's that the currently selected one is not even shown in red, even if it switches in AI Server or even in One Shot. It'll be black, focus confirm blinks it red then back to black, and then stays black.
Isn't that what my 5D and 20D do as well? I'm trying to figure out why this bothers anyone when I've shot >100,000 shots with mine with never a thought. Do the points look different when unlit on these newer cameras than they do on mine?
Yes, it's the same behavior. I do fairly well with the black AF point, but I do lose it sometimes when shooting HS football, which is always in the dark. Of course, that was center AF point only. With the multiple, usable AF points of the 5D3, that just adds difficulty to keeping the correct point on the subject.