Increasing awareness that popular functionals fail to describe many energies accurately has ended expectations of black-box DFT usage. The performance of nine d. functionals, compared by computing the bond sepn. energies of 72 illustrative hydrocarbons with available exptl. data, reveals that only Zhao and Truhlar's recently proposed M05-2X functional, with a 2.13 kcal/mol av. deviation from expt., performs satisfactorily. B3LYP and other functionals show larger deviations. [on SciFinder (R)]