Your post was really good. Just a couple of observations that are not nearly as eloquent as what you wrote:

1) You are trying to mix logic into law and guidance.  Much of the tax code has no logic. Hence we have things like AMT, tax cliffs, etc.

2) Regarding your  #5. What is the point of a "completed gift" then? Even if it is only a paper trail, there has to be a difference in gifting a child $15k and them using it for tuition vs. you paying the $15k to the institution.