great theory - BUT - isn't there always a but
the issue is - which ever gun I am looking at would be gone by the time the gauge arrived.
funny - just today I was putting together a list of what I would put in a shotgunner addict version of a bug out bag.
The Skeets bore gauge (finally found one, be here in a day or two), a set of digital calipers, a tape, and a wall thickness guage, and maybe a copy of the serial number book. cafefully packed in a carry case, it would go in the back of the truck any weekend we were not stuck with chores at home.
I have passed on five questionable damacus SXS's (two were Parkers) in the past year or so. both Parkers had been honed - no tools - no idea how much, not taking the chance. I run into these sorts of things when least expected and in some odd places. I still might not buy them - but they won't haunt me ( I hate being haunted
)
Back to the topic of the post - it is not a bad idea, really it could work in some situations- if the buyer could put a gun on hold at a shop, or had one coming with an inspection period from a on line source, access to a wall thickness gauge within a couple days - could be handy