So, what am I going to do?
I could contact Victorinox and try to persuade them to refund me the wrongly charged German VAT. What do you think? Likely to be successful? Seems like a probable hiding to nothing.
Even if the above was successful, I'd still need to pay the current import taxes due and then try to get the £19.39 overpayment on those refunded. Whilst Border Force have in my experience been helpful in issuing refunds in the case of their own errors, this one is more complicated. They have in fact correctly calculated the taxes due on the basis of the declaration given to them (apart from apparently rounding up the net basis from £352 to £360).
The obvious alternative is to wait for Parcelforce to send the item back and then eventually get a full refund out of Victorinox. Luckily I paid via PayPal and so I can force a refund that way should it be necessary.
As an aside, I presume that the package includes a paper invoice. I'd love to see what is written on that (e.g. how much VAT paid and to whom) but I can't get to see that unless I pay the current import taxes due.
In the meantime, the takeaway point is this:
IF YOU ARE IN THE UK, DO NOT PLACE ORDERS VALUED AT MORE THAN £135 FROM VICTORINOX.COM.
THEY WILL OVERHCHARGE YOU BY WRONGLY CHARGING GERMAN VAT AT 19% AND, AS A CONSEQUENCE, FORCE YOU TO PAY MORE UK IMPORT TAXES THAN SHOULD BE DUE.
What do you think I should do?
In summary, I am being required to overpay by a total of £75.59 (£56.20 overcharge by Victorinox plus £19.39 extra import taxes).