NavList:

Sean,

You wrote:
"The idea is that, at any given time, the actual slope of a body's changing alitude (or, in this case, apparent distance from the moon) can be calculated and compared with one's observations."
And added:
"Do you think I would get a more accurate fit if I somehow worked parallax back into the calculated distances"

Aha. Yes, I wondered if that was what you were talking about. The geocentric, cleared distances change at a rate that is significantly different from the rate at which the observed distances change. Unlike celestial altitudes, lunar distances are affected by the corrections, primarily lunar parallax as you suspected, at a rate that is a substantial fraction of the base rate. Please tell me if that makes sense, as words, and then I would be happy to get into quantitative details (and you can, no doubt, do so yourself if we are on the same page as far as this verbal description goes).

Frank Reed