We have, elsewhere in this same thread, reports of bad data delivered as good, and causing trouble, Mr. Phillips's opinion notwithstanding. The incidence is, therefore, not negligible for data many people care about. Partially-written blocks are only one cause of bad sectors, which I noted only because they are an example on one that occurs much for frequently for some users than for others. Bad sectors may occur in the journal as well as in file contents. The drive will detect and report only a large, but not always a large enough, fraction of these.