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"Gadfly":

First, please allow me to decide what I will or will not do, or whether I think the discussion is worth it. (I don't mean any disrespect in this, nor do I say this with any degree of anger.)

Secondly, when one is dealing with curved spacetime, there really are no "inertial reference frames" available or definable. In fact, in one of my textbooks on General Relativity (that, unfortunately, I left in my office at work) there is a good quote concerning how the fact that all observers must deal with being in non-inertial reference frames actually accomplishes Einstein's desired goal of the "relativity of acceleration". (Incidentally, Jim's response to you about how both of the situations you present [from Einstein] involve "inertial accelerations" is correct [though he is not entirely* correct about a uniform gravitational field having no "magnitude"].)

David

* He is correct that a uniform gravitational field (devoid of curvature), in the absence of any other references, has an arbitrary "magnitude" (including zero). However, depending on other circumstances, like the distribution of mass-energy-momentum-stress surrounding the location in question, there may, indeed, be a definable magnitude.