I have never understood this need for fallacious statements. Flexible bodywork has always been legal within the prescribed limits. And just for the sake of making things clear, while some are trying hard to muddy everything, here is what the FIA F1 technical regulations specify: http://argent.fia.com/web/fia-public.nsf/15A68242E9992FCEC12577F8004A826A/$FILE/1-2011%20TECHNICAL%20REGULATIONS%2010-12-2010.pdf And the reason for these regulation is that there is no 100% rigid material to be used.