-The @value{op-unlink-first} option removes existing files, symbolic links,
-empty directories, devices, etc., @emph{prior} to extracting over them.
-In particular, using this option will prevent replacing an already existing
-symbolic link by the name of an extracted file, since the link itself
-is removed prior to the extraction, rather than the file it points to.
-On some systems, the backing store for the executable @emph{is} the
-original program text. You could use the @value{op-unlink-first} option
-to prevent segmentation violations or other woes when extracting arbitrary
-executables over currently running copies. Note that if something goes
-wrong with the extraction and you @emph{did} use this option, you might
-end up with no file at all. Without this option, if something goes wrong
-with the extraction, the existing file is not overwritten and preserved.
+The @value{op-unlink-first} option causes @command{tar} to always
+attempt to remove a file unconditionally before attempting to extract
+it. This can make @command{tar} run a bit faster if you know in advance
+that the extracted files all need to be removed. Normally this option
+slows @command{tar} tar down slightly, so it is disabled by default.