The ability of AF to deliver accurate focusing v MF is interesting. When sports photographers used analogue cameras, such as the F5, my impression was that nearly all the pics they took were in focus. If it was less than 50% then the photographers were wasting 50% of their films and presumably the hight burst rate of shooting that the F5 was capable of would not have helped.
So it seems that out of focus sports shots in newspaper and magazines should have been much more common than they seemed to be. I have never seen any articles saying that the likes of the F5 had only at best a 50% reliablilty and that a lot of film was wasted but that whereas the digital AFs were no better, the ability to shoot in a virtual unlimited fashion with a high MB card now saved them from having to settle for an out of focus picture
Anecdotally and turning now to my own system( Pentax) I rely on the green signal that appears in the viewfinder to tell me that I have my target in focus. I have frequently tried the same AF lens in the MF setting first then thrown the switch to AF and in every case the AF focusing was accurate.
What I have found is that occasionally I have allowed the AF system to focus on the wrong part of the scenes so what I wanted to be in sharp focus wasn't but this was a combination of a system that had a very limited range of focus points compared to the likes of the much more sophisticated F5 and my not paying enough attention to what the focus point had settled on.