What I have known is that the powder, because if it breaking from bouncing off itself in the sealed casing, changes it's burn rate if tumbled too long.
The fact that the burn rate of the powder could possibly change, also increases the chance of elevated pressures in said cartridge.
I have personally never experienced it, but will take the advise of those that warn against it.
I have never jumped off a bridge either, but will take the advise of those who warn against that too.
Chris in NH.
"some days, I wish my dogs could talk"