I think you are a bit more likely to notice in a CSV/TSV, as it is unlikely to truncate at a newline?

Still, fair point. And is part of why I said it is a flaw, not the flaw. Plenty of other reasons to not like YAML, to me. :D

Not if it is split at a line e.g. if the source or target can only deal with a fixed number of lines.

Right, that is what I meant about that being unlikely? Most instances of truncated files that I have seen were because of size, not lines.

Still, a fair point.

Really depends on how the CSV is generated/transferred. If the output of the faulting software is line-buffered then it's quite likely that a failure would terminate the file at a line break.