2009/2/19 Jussi-Ville Heiskanen cimonavaro@gmail.com:
Without disagreeing on the importance of attribution standards per se, it is clearly inaccurate to say that they signify how we interpret the license. Contributors can be asked to waive rights to content they add to the site (where they are the sole originators of the material, and not merely importing content that has already been published elsewhere) even above and beyond the terms of the specific license, and equally they can be asked to not pursue some rights specified
That can't be done with any content added to wikipedia prior to the license update makeing such waive useless if not actively damaging.