WeprovethatforeveryLipschitzisomorphismffromaseparableHilbertspaceHtoaBanachspaceYwithRadon-Nikodymproperty,thereisaboundedsurjectivelinearoperatorT:H→Ysothat(f+T)-1(NG(f-1))isaΓ-nullsetofH,whereNG(f-1)isthesetofallthepointsofGteauxnon-differentiabilityoff-1.