> if someone can't figure out how to extract a tar archive just from looking at the synopsis on the man page and scrolling through the options, unless the archive was maliciously named to hide the fact that it's gzipped or something

At least with GNU tar (and I think Darwin and some others), compression doesn't matter any more; `tar -xf foo.tar` correctly autodetects the compression and extracts even when foo.tar is gzipped.