If you're working on a cure for cancer you should have double, triple, quadruple backups on and off site and not fly around with the only copy of your data.

I bet GP meant it to ironic. That said, having a backup and knowing that the data was just corrupted are two different things. In a word without storage level CRC checks, it is possible an otherwise successful test is overlooked and we move on to 'n + 1' in the iteration.

But that said, hopefully all filesystems have some sort of error to show the file has been damaged.

"Plans to turn TSA scanner into radiation therapy machine corrupted inside TSA scanner."

Damn, that was the only copy.