I think his advice will be different when discussing macro focus stacking. I haven't gotten to that part yet.That's a waste in my mind in situations when there is no infinity to "stop" the camera and even in some situations where the lens can focus at infinity. Capturing four to six times more images than is needed will cause the shutter to die sooner than is necessary. Thought that may not be a practical concern, one never knows until the shutter has died whether it should have been a concern. After getting used to the number of captures that are needed in a given situation, my experience is that we can narrow the number of images down to no more than twice as many as are needed.
And of course when the Z5, Z6, or Z7 are set to silent shutter mode, which he recommends for focus shift shooting, there is no physical shutter movement.