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That's an interesting analysis--maybe complete and correct, maybe not.

The dates I listed for the various models are just the dates of the ads that we currently have and do not necessarily reflect the only year(s) each model was produced.  Also, given that these models are pre-1950, the only date available is on the movement, rather than on the case, so, if we use date alone for ID, we may be identifying a watch based on a movement that was not original to it.  That's why I believe, that, given their similar case shape, dimensions may be helpful at some point in determining which model one has.  I've noticed a bunch of these case shapes for sale on eBay recently.  This question may require some attention in the future.