Thanks, Doug - there are certainly are lot of nuances to that kind of information that could be abused/misused/misinterpreted by a regulator.
I asked the question from a "solution in search of a problem" perspective - is there any documented indication of a safety problem from unproofed guns that might warrant the need for a proof house?
Of course, if you wanted to promote proof houses, offer makers an absolute defense to product liability for proofed barrels. If the barrels pass proof, any subsequent malfunction would be deemed the result of operator error. (That approach ignores the question about how much proofing weakens barrels).
Gun proofing reflects the philosophical divide between the US and Europe on the regulation of risks generally. In Europe, there is risk until proven otherwise. In the US, there is no risk until it is proven. Europe uses bureaucrats to regulate risk, we use trial lawyers.
