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We comment on two recent calculations of the second order perturbativecorrections in the heavy flavor semileptonic transitions within theBrodsky-Lepage-Mackenzie approach. It is pointed out that the results do notshow significant enhancement either in the inclusive $b\rightarrow c$ decays orin the exclusive amplitudes at zero recoil provided that the expansionparameter is chosen in a way appropriate to the kinematics at hand. The valuesof the second-order coefficients inferred from the BLM-type calculations appearto be of order unity in the both cases. Thus, in both cases no significantuncertainty in extracting $V_{cb}$ can be attributed to perturbative effects.The theoretical accuracy is mostly determined by the existing uncertainty in$1/m_c^2$ nonperturbative corrections in the exclusive $B\rightarrow D^*$amplitude, and, to a lesser extent, by the uncertainty in the estimated valueof the kinetic energy matrix element $\mu_\pi^2$ in the case of $\Gamma_{\rmsl}(b\rightarrow c)$. The theoretical accuracy of the inclusive method ofdetermination of $V_{cb}$ seemingly competes with and even exceeds theexperimental accuracy.Comment: 9 pages, no figures, revised: One reference added and some styllistic  changes mad

A CLOSER LOOK AT PERTURBATIVE CORRECTIONS IN THE b→c SEMILEPTONIC TRANSITIONS