Canon EOS 70D Jumping Horse Challenge
And jumping horses did seem to be a challenge to the 70D's AF system. The 70D's AF is customizable available via the custom functions menu. If I spent enough time dialing this camera in for this AF challenge, I expect that my results would have been better. The out-of-the-box settings delivered somewhat below expectation in this particular situation. Obviously not all results were out of focus.
Camera and Lens Settings
70mm f/2.8 1/1600s ISO 320 3648 x 5472px