Pople basis sets remain workhorses in DFT and it is therefore interesting to note that in order to reduce convergence errors below 1.0 kcal/mol, CP correction is required in most (though not all) cases. With the exception of the slowly-convergence M06-L functional, convergence errors for all CP-corrected functionals are 0.5 kcal/mol. These errors are systematically smaller when diffuse functions are added, yet CP correction is still required to reduce the convergence error to something comparable to the intrinsic accuracy of the functional in the DFT/CBS limit.