In general I only use auto-focus for moving subjects. The DOF preview button is an old friend, and I use that in concert with manual focus for landscapes or to set what I call “photo traps” for moving subjects within a larger landscape view- I.e., selecting and setting a focus for the larger scene, within which the subject is moving. Due to the darkening through the viewfinder when pressing the DOF preview and closing down the aperture, I’m much more inclined to put a hood on the viewfinder. It’s really critical for my methods in selecting apertures for specific DOF. For folks who rely on their screen for critical image adjustments, I’d see the same value in a Hoodman Loupe.
Dunno if my explanation makes a bit of sense. But in this recent example of very close California gray whales, I was able to “pattern” their movements and appearance and pre-focus on the spot (effectively setting my trap) while waiting for the whale to make it’s brief appearance. A quick adjustment for framing and I was done. Autofocus was simply too unreliable, what with all the moving water and problematic DOF adjustments to keep the whole whale in focus.