Yes, I feel a little better now after reading all of this. My exprience is somewhat the same. I use 2 bodies when I was doing parades and festivals. One night I switched both to the rear thumb button for AF (a good idea.) Drove 100+ miles to a small town north of here for thier parade. Parked at the end of the parade route. Wlaked the entire 2+ mile route to the beginning to get pix of everyone getting ready. 90F that day and I am not young. Went to take my first shot and AF was not coming on. Good thing I carry 2 bodies, eh? Tried 2nd camera and same thing! What are the odds of 2 cameras breaking at the same time? Walked back to my car, drove home, had a few drinks before I realized what had happend. Reset both bodies to work the "normal" way. Waited 3 weeks and tried it again - switching AF to rear button only. Same routine, new city, another 2+ mile parade route. Darn if both cameras were broke gain. Drove home. Desided thia was just not working. I waited until I bought 2 new bodies at the same time and out of the box I made both only AF with the rear button. NO problem. I knew how these new cameras worked and was never confused (in that way) again. Gene