I certainly don't intent to demean the profession as I am a cfi/meii and I am aware of what else goes into instructing but the basic premise I'm getting at is as a flight instructor my hands, although a quarter inch from the controls at any given time, arent necessarily on the controls. If you do safety pilot time properly your eyes should be on everything: outside, inside, instruments, navigation, charts, radios. If you do all the stuff that you should be doing then safety pilot time can be very beneficial. It also lets you observe the other individual flying and see what they do that works and what they do that doesn't work. A lot of cfi's say they learned more after they started teaching then they did going through training because of what i mentioned above and switching with someone as a safety pilot can be beneficial for the same reasons. That 'correalation' level has what has really hit me as a cfi watching my students do things.