Interesting comment. I'll give you my reactions, though I'm not sure if you're being critical of Lange's marketing, of the auction house's marketing, or of the watch itself.
You asked, "Why single out a point that makes no sense whatever except for a believer in the company and its press releases?"
One good reason that marketing departments make hyperbolic statements is to arouse curiosity in potential buyers, to get them more interested in the company's products. For me, this particular marketing statement raises several questions. How is this moonphase different from moonphase indicators in other watches (including other Lange watches)? And if this moonphase indicator is different (more accurate, etc.), then how did Lange achieve this difference?
If arousing curiosity was Lange's goal, then I'd say it worked quite well, as evidenced by the various conversations that have occurred on various Lange discussion forums (and in various dealers' showrooms) over the past 14 years since the watch was launched.
I do think there's a NON-VERBAL dimension to consider regarding your statement/question, "That is a major selling point and they have nothing better to offer us [than mentioning claimed moonphase accuracy] - even as a highlight?" I'd say yes indeed, the only functional marketing feature of the 1815 Moonphase is its moonphase. There really ISN'T anything else functional to talk about because the watch does absolutely nothing else except tell time. The moonphase is its only complication. BUT there is a whole other dimension that Lange can and does offer us with regard to the 1815 Moonphase: The aesthetic of the watch, i.e., how it looks when you see it, and how it feels when it's on your wrist. I would suggest that THIS is the "major selling point" and the very best thing the company has to offer us when it comes to this watch, and it transcends words ("a picture's worth a thousand words"). Indeed, for me, that's the beauty of the 1815 Moonphase and several other Lange models: No matter how eloquently a poet can wax (no pun intended) fondly about a watch, or no matter how articulately a watchmaker/WIS can describe its technical details, and no matter how cleverly a marketing employee can capture its selling points -- in the end, it is the look and feel of certain Lange timepieces that capture both my heart and my head. For me, that's a MUCH more powerful and effective means of marketing than a mere verbal statement about moonphase accuracy.
[By the way, I like posts such as the one you made here because it is provocative and critical but not personally offensive or attacking.]
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