~ With a wealth of experienced, well-informed members in the Montblanc Forum, I'll be promptly corrected with more accurate information, if what I write is flawed.
I'd been told by both local Chinese boutique staff and senior management of Montblanc China that the great majority of repairs, nib exchanges and any part replacements were performed in the Shanghai service center.
They went so far as to show me the paperwork — not in 中文/written Chinese but rather in English — required to request parts from Hamburg for work to be performed by technicians in Shanghai.
Nearly all nib exchanges are performed in the Shanghai service center by a team of Hamburg-trained technicians. They also repair basic issues with Montblanc leatherwork and timepieces.
As to writing instruments, in general, the only situations in Montblanc China wherein the entire pen is shipped to Hamburg for work are as follows:
• Nib exchanges for limited or special editions
• Substantial reconstruction of damaged pens
• All OBBB nib exchanges
• Any special request by the Montblanc China Regional Director
To ensure that the work performed by the technical staff in the Shanghai service center reflects Hamburg's standards, any pen must be triple inspected, i.e. examined and fully checked out as to functionality and loupe examination, by competent personnel prior to be returned to the boutique nearest to the client.
Accordingly, not much after service work is performed in Montblanc's Hamburg workshops for Montblanc China's clientele.
Anything about other Montblanc regions around the globe would be no more than my uninformed conjecture and hence worthless.
If any of them are organized along the lines of Montblanc China, then most nib exchanges are performed at the respective service centers in those regions, rather than in Hamburg.
Hence there's sound reason to wonder about the procedures and quality control in the Montblanc USA service center where so many of the problems seem to originate.
By all means, please stringently correct me if what I've posted is in any sense misleading or irrelevant to practices elsewhere.