Real world stuff there are thoudands of types of the same size fastener depending on wear and abuse to who spec'ed what when it was built. Or who didn't care less about specs or tool choices in fixing it.
Lab testing with prepared damaged fasteners is merely a good start. Getting them in the field into indy shops where any POS may be pushed in could offer a very wide range of messed up to test on.
Grade 8 on most things would be a treat for me. I get all manner of useless fasteners in and try to replace with better from the bucket if we have them. Because it will be back sooner or later.
Farmers would be the acid test. They got the full load of old mixed up whatever worked to keep it going.
