I can't seem to get anything this sharp out of my 5D3-hmmm.Earlier on when I got my 5D3 first, may shots were not sharp. Some were due to not doing the AFMA and others were due to camera shake. I have doubled the shutter speed since and that helps. Also body sway while shooting wide open can mess things up so I shoot AI Servo many times.
That is so true! The first test shots were really disappointing! I did exactly what you did - doubled my shutter speed and AFMA'd my lenses...
That's actually important. I even noticed a difference from 1/1600s to 1/5000s during football games using a 400 f/2.8 lens with IS OFF. I was surprised there was a difference when shooting that fast anyways, but there is.