More on, "push" / "pull", Pre-load, and "Prepping the rod"- "Poised wrist"

Your explanation is much more explicit and correct from a physics standpoint. The fact remains, however, that with most students....even advanced casting students, the concept using the words, "push" and "pull" DOES seem to get the desired result across however technically inaccurate it may be. The wording you used, "...poised wrist" I think is a good teaching term, too.

I know that you excel at teaching fly casting. If you choose to use the term "linear" then fine but I add that "linear" is a fairly obscure word because its major context is in describing mathematical features. I think many people would be forced to guess what it means if they were asked (perhaps a common reply might be "straight"?). But I'm sure that when you go through your descriptions they pickup the context you want them to.

On the push-pull thing it seems to me that not even most certified casting instructors know what the real story is and it must be pretty obscure to students. If you mean to say "don't rotate the wrist until you get to business" then my opinion is to say that instead of speaking in intangibles. One person's "pull" can easily be the next person's "push". I personally often speak of maintaining a "poised wrist" up to the point (position in space) where it is to be used and describe what I am doing as I do it. Motion up to that position has as one of its goals prepping the rod so that more energy transfer can occur during the 2nd and 3rd phases of the cast. A very important thing for the students to learn is that the rod should be loaded (I think "preload" adds valuable context) prior to applying wrist inputs -- particularly for more advanced students who are trying to achieve a higher level of performance.