All I'm talking about is dampening the strings slightly and then reducing the dampening effect by sliding the palm of my hand back towards the bridge. This does involve harmonics but only in the same respect that dampening does, by dampening a string you reduce the volumes of both the fundamental note and its overtones, particularly the higher overtones which are reduced to below the threshold of hearing sensitivity.
If you try it you will find that you can get a slight wah effect on an acoustic guitar, something I found most surprising.
If I couldn't laugh at myself how could I laugh at someone less ridiculous?