Posted By:
Tim NewcombHaving received a couple of skeptical questions, let me clarify:
I tried to indicate my own skepticism about this-- I'm just reporting what I was told. I have no interest in the matter-- who cares about postwar dreck like 1952 Topps anyway? 
The rest of the story goes like this:
I WAS TOLD 
that the single pack opened in 1952 was still with the box when it came to Mastro. The dealer I was speaking with named the cards supposedly in that opened pack, although I've now forgotten who they were-- commons as I remember, but at least a couple were high numbers-- so I WAS TOLD.
Supposedly the kid preferred the smaller Bowmans and never took an interest in the whopping great Topps cards, so the box was just packed away for all this time. Etc. Etc.
I don't doubt that Mastro routinely hypes things disproportionately, but THEY ARE CLAIMING that the provenance of this opened pack indicates what's in the box.
Again, I don't take a position on the validity of this claim myself. If I were Mastro, however, I'd hesitate to make the claim knowing that at least some of the packs are bound to be opened by the winning bidders.
A 1952 Topps pack is totally unlike a 1960 pack, especially if it contains high numbers. The claim that high numbers are involved will surely make it MORE likely that some packs will be opened in search of a PSA 10 Mantle (triple-printed, after all)
FWIW
glad to have found a way to enliven some of your mornings
Tim