Comment #3 on issue 3079 by [email protected]: Add support for `real' dimensions? http://code.google.com/p/lilypond/issues/detail?id=3079
I don't see how we could make "\realcm" have any reasonable meaning in the presence of different x and y scale factors and rotations. TeX does not have these complications: it only has a global \magnification factor, and indeed, "real" works by premultiplying with the inverse \magnification.
