[Senior Patek Moderator]
I wasn't going to reply, as I think everyone should have their opinion, and this really isn't about Lange's level of movement finishing, or a comparison with Patek, AP, or anyone else.
However, I was searching how this whole discussion originated, and look who started it less than two months ago:
Now, all of a sudden, Lange "has always made it clear", "there shouldn't be a confusion", or it's even "indisputable", etc... but until this epiphany, note that you were asking the exact same question that all Lange (or ex Lange) fans have legitimately asked in the last two threads of this forum: "Doesn’t Lange insist that every part seen or unseen is finished to the highest standards?" And then, equally reasonable, "Upon learning that the underside of the hands are not finished, i have to admit that I felt somewhat betrayed” (also your words, just five days ago).
This was to set the record straight, whichever your good reasons to be Lange's staunchest defender now. Given this, I sincerely hope Lange can still provide to their customers a transparent and convincing explanation -- or certainly, one that's less self-destructive than how you reported their words, that "proper functioning cannot be guaranteed" for the components they don't manufacture.
If your contact or any other individual authorized to speak on behalf of Lange wishes to send us an official statement, we'll be happy to publish it on our forum. So everyone will finally be able to make up their mind independently about Lange's own explanation.