If Cat is willing to put one up then so am I.
A number of years ago I made a classic mistake that was warned about many times. I unknowingly substituted IMR 4831 for H 4831 powder. Didn't blow anything up but got some impressive over pressured cases and a 270 with huge recoil. And same as Cat I could not for the life of me remember at what point I had switched powders so I ended up pulling a bunch of bullets and dumping some powder. All my data showed all the pertinent info EXCEPT when I switched powder cans.
Regards,
Dave.