No they are not. The center point and the two points above and below it are better than all the rest of the points. They are cross-type + diagonal + high precision sensors when a f//2.8 or faster lens is attached, and just cross-type with slower lenses (up to f/5.6). The next best points are the 16 immediately surrounding those 5 points, which are cross-type sensors whenever an f/5.6 or faster lens is attached. Then there are the 20 points making up the center two columns of the outer 40 points (10 center points of the 20 points on each side), which are cross-type sensors when an f/4 or faster lens is attached. Finally there are the remaining 20 points, outermost and 4th colum in on each side, which are not cross-type ever.
So actually the outer points are the worst, and if you have a slow lens the entire outer zones are not that great.
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Technically yes, but I think he meant in practice...