Robert Fitzsimons [off-list ref] writes:
Allow the user to force a patch that deletes a file to succeed even
though the file might still contain data. Added a test case.
Why?
I've seen cases where git-apply incorrectly thinks a patch
leaves some data in a file to be deleted, when incomplete lines
are involved. But I think that bug has been fixed, and the only
case where you would need this new flag should be dealing with a
corrupt/invalid patch.