Ah! I see filipo,
what a delightful heirloom.
I can see your point.
Bujutsu, it's still hard to say,
we tend to only beleieve what is in print,
but even that is incorrect sometimes.
I think the debate is still open.
Personally, I imagine a clerk, somewhere down the line
when spotting a cover that has been cancelled, but has missed
one particular stamp in another part of the cover,
runs the roller over it, but that is just guessing.
A reply from Ryan, a member of SCF in 2009 I think.....
My copy of the last mentioned precancel catalogue above contains no
reference (that I can find) to the "pizza wheel".
My 2007 "Officiële Belgische Postzegelcatalogus" contains the
following text (presented in the original - I struggle with Dutch /
Flemish, similar enough to German that I can sort of figure it out but
different enough that I'm never too sure):
"Vanaf 10-12-1869 treft men roulette afstempelingen aan van de spaarkas
om zegels te ontwaarden." (accompanied by graphic of the cancellation)
Best guess is that this means the cancellation began in December
1869, used on stamps cancelled at the post office savings bank.
This article on Belgian precancels mentions the savings bank
cancellation only in regard to being a second cancel, similar to US
precancels that then get a regular postal cancellation stamped over top