I was pointing the outer focusing at the face towards the eye and even if I missed it by little it was much better than ruining the composition by trying to use the center focus point at the eye or keeping the composition and using the center point to focus somewhere else.80% = About 8 pictures out of 10 since I could not even see where I was focusing with my eyes! In these 2 attempts the camera had refused to focus, it didn't focus inaccurately. Simple as that. And yes I was that close. Plus there was movement in the dark.Yesterday night I was able to take some pictures at a bar with almost no light. I had my 5D3 with 35mm 1.4L.
I was using an off center point and I was amazed that it was able to focus 80% of the time when I couldn't almost see anything with my eyes! I understand that I wasn't close to EV0 but still I was impressed (ISO was either 25K or 50K , f was set to 1.4, speed 80 to 100 and compensation was at +2/3 stop) OK I wasn't going for a masterpiece but for snapshots with lots of noise. The camera/lens combination delivered. I do not know if 6D could do that (off-center focus under these conditions)...
Frankly I don't believe off center focus was vital in your scenario. Post some of the pictures, to help prove otherwise. Focusing at a distance of 5 feet or more, is not going to make a big difference if you focus then recompose. If the focal plane is less than 5 feet (with the 35mm lens), then I could see requiring the off center focus points. But focusing accurately 80% of the time, is not as good as focusing accurately in low light 100% of the time with the 6D's center point, then recomposing. And don't quote the above out of context without this part: For that particular lens, it's likely the 5D3 is a better overall match, especially if you must use AF points outside the center. But as you said, in low light, the 5D3 has some trouble...missing focus for 20% of the shots.
Gotcha...but if you need to focus on things you can't even see through the viewfinder, the 6D's center point is always going to achieve focus...usually quite accurate as long as you use multiple half press. If you're just swinging the camera around and running here or there or something, in the dark...and don't take the extra time to make sure the focus is right...then you should be glad you got any usable shots at all.
You have such a strong opinion for a situation you weren't in front - and true I hadn't described 100% because I never thought I had to - that apart from a Canon super expert you seem to behave like a psychic or something
My mind can take me places, just tried to envision the situation. Not a psychic. I'll take you at your word...but unless you tried the 6D in the exact same situation, and focus-recomposed, how can you be so sure the focus would not have been as close as it otherwise was? Were the shots all at wide open, f/1.4? You realize there is a bit of focus shift with such lenses, if the aperture is not wide open...because those precious focus points are focusing while wide open. Were you able to get a fast shutter speed? Were the people moving or did they stand still and pose as you shot them?