The question is: Given a dozen of simply formatted text documents, given they'll all carry the same license, given most of them will but a few will not come with the .tex, given the author wants anyone to have the 4 freedoms (as conveniently as possible under this restrictions), is it better to put "All rights reserved" (status quo), a CC license or the FDL?
`a CC license' includes a class of non-free documentation licenses that for example prohibit you from using them commercially, and other nasty things. `All rights reserved' is also a non-free documentation license as well, so the only choice is really the GNU Free Documentation License.
One position is "if it's not ultimately free, dismiss it." (And some count FDL as *non*free.) I rather support "make it as free as possible. Then keep improving."
They count it as a non-free _software_ license, which it is true, since it isn't a software license to begin with; it is a documentation license, and a free one at that.
Cheers!