We normally start teaching the locks in the most prearranged, static and non threatening situation one can imagine - a simple wrist grab, or dash grab, with very well directed minor pressure in the grab (which actually helps the Kuzushi). The beginner then progresses to dynamic grabs - adding a timing element, but still no threat. The next stage would be Shomen Uchi or Yokomen uchi, since in these strikes it is easier to read and the lines of power are very well defined. And then we progress on to teach those techniques in various punching situations etc.