Thanks Michael. I certainly defer to your experience, and particularly when it comes to pocket watches. However, your response does beg some further parsing of the semantic question.
You have seen around 50 with a "chronometer" designation, presumably over decades, with an obvious brand focus, and having enjoyed special access to the Manufacturer, etc. So, even if one were to assume that there were at least double that number produced with such dials, let's bring some context into the discussion.
Having had a quick look at your excellent work on the IWC pocket watch site, I see that there were almost 300,000 Calibre 53 watches produced. Then, I see roughly 38,000 of the cal. 66, 67,000 of cal. 74 and 74 models, 10,000 cal. 77, and 25,000 of cal. 95 and 97. So, excluding ladies models and the ones that you characterized as "less expensive", IWC produced at least 440,000 pocket watches up until around 1960.
While I again admit that these are rough calculations, given that we have no precise ides how many more that the 50 chronometer dials that you have seen were actually produced, if there were 100, then they would represent 0.000227 of total production. Double that number (i.e. 200 produced) and the number would be 0.00045.
To my mind, such very small numbers do denote rarity, though I would be interested to learn why you might disagree.
I would also be interested to hear you comment on those, as a group, that you have seen with such designations. Would it be fair to assume that the movements found in those watches were of a high grade, and highly finished? Do you have any doubt that they would have been capable of receiving third-party certifications?
Thank you.
Regards,
Tony C.