Hi Edwin,
With the effectively entertaining device of a stage play taking place in a bar, you've revisited a variety of "relativistic" debates from a range of perspectives (historical characters).
As an indicator of where I stand in such matters, I'll begin by offering my translation of the recurring relativistic expression: "Relativity of Simultaneity." As used by Big Al and his troupe of loyal followers, what I think the idea really means is this:
Fogification of the inevitability of the anisotropy of light propagation.
As any competent ether theorist would argue, since light propagates as a wave in a medium, at every point in space there is a frame of reference (speed and direction) with respect to which light speed equals exactly c. Which means it equals something else in all other frames.
A point not often enough appreciated in such discussions is the huge difference between one-way speed and back-and-forth average speed. Locally, the back-and-forth average speed has so far always come out to equal c (Lorentz invariance). Whereas the one-way speed is arguably impossible to measure, due perhaps most of all, to the problem of producing a pair of synchronized clocks at the endpoints of the path.
Typically, the discussion gets very messy and fraught with all kinds of misunderstandings. In the interest of simplifying things, I've often conceived of a vast empty space with two props, considered one after the other: 1) a rotating wheel and 2) a massive sphere. In the first case light speed anisotropy can be measured because a light path can be made to follow the circumference in opposite directions. Return times to the same starting point are not equal. Also, time dilation is shown to be non-reciprocal: slowest clocks on the rim, fastest clocks at rest with respect to the axis. These are facts.
In preparation for considering the second case, you may recall that, upon contemplating such problems, wherein Earth's gravity has to be accounted for, Phipps sometimes use the expression: "born-and-bred inertial clocks." I think this is a step in the right direction, as is your idea of conceiving "light propagating in local gravity defin[ing] the preferred frame."
Neither approach, as I see it, is sufficient to the task, however, because of abundant evidence provided by motion-sensing devices (accelerometers and clocks) that almost all such frames still yield evidence of motion. Neither Phipps' idea, nor yours, are sufficiently restrictive.
Intent on cutting through the complications, it long ago occurred to me that the answer is to identify the general (gravity-inclusive) analog of the rotation axis. The most strictly "born-and-bred inertial clocks" of all are members of the family of clocks that are falling from infinity. This is the collection of "preferred frames" whose trajectories I call maximal geodesics.
Disentangling maximal geodesics that might serve as such with respect to one massive body from the influence of other bodies and all manner of rotational and linear motions in the real world is no trivial task. But I think it's the appropriate strategy.
Upon pursing this route, I think it is interesting that, even accepting the possible fundamental significance of radial falls from infinity, we encounter a seemingly irreconcilable conundrum under the assumption that gravity is an attraction. If the paths are followed into a hole through the center of the source mass---if gravity is regarded as an attraction---then we'd have substantial speeds with respect to the center in every direction. Accelerometers on these trajectories NEVER gave non-zero readings. So how did they acquire any absolute (non-preferred) speed? Presumably, the rates of such clocks whipping past a clock at the center would be slower than the central clock. If these clocks never suffered an accelerometer-measurable acceleration, then what made this happen? Gravitons? Purple-winged horsies?
As you know, my model avoids this conundrum by steadfastly adhering to the testable prediction that trajectories representing radial falls from infinity do not pass the center. A clock at infinity and a clock at the center always tick at the same rate because they are extreme members of the family of maximal geodesic clocks.
I'll leave it at that.
Best regards,
Richard Benish