It might be sacrilege to say this, but autofocus is overrated. And I'm speaking as someone who routinely shoots with a pro sports camera (Canon 1DmkIIn). Yes, there are times when the combination of a pro body and L series lens can produce amazing results, but often those results are just as much a credit to pre-focusing, planning and anticipation. The fastest autofocus in the world won't help if you're focussing on the backfield in a football game when it's third and 20 and the situation favors a long pass or when you're focussing on a nearby tree branch and a bird flies by.
Overriding autofocus becomes particularly important when you're trying to emphasize one part of the image over any other. Often it's your control as the photographer that makes that choice. Sure, you can let the autofocus sensor focus on your subject, press the focus lock button and recompose the shot, but personally, I'd just as soon turn autofocus off and do it myself. Autofocus is just about completely unnecessary for landscape photography where you're usually shooting at hyperfocal distance anyway.