The paper is organized as follows. We first present the computational methodology including a brief description of the CBH approach. Next we discuss the accuracy of the predicted reaction enthalpies as compared to G4 reference values for the 25 reactions used by Sengupta and Raghavachari and perform an error analysis of outliers by comparing heats of formation of the CBH fragments to G4 values. Finally we summarize our conclusions and discuss their potential implications for parameterization of semi-empirical methods. shows the mean unsigned error (MUE) relative to G4 reaction enthalpies for the parent reaction (Dev-0) and the CBH-1 (Dev-1) and the CBH-2 (Dev-2) correction schemes. In addition the maximum absolute error for the CBH-2 scheme is also listed. As observed in the Sengupta and Raghavachari 1 study CBH-1 correction scheme provides only a modest improvement in accuracy and for many of the semi-empirical methods the error actually increases. We will return the source of the error-increase in the next subsection, but for now we will focus on the accuracy of the CBH-2 results.