Any model makes some inaccurate predictions but models can retain utility despite significant propensities for inaccuracy. Inaccurate predictions aid the choice of models for future predictions. Because of this, the central scientific problem in the computational study of the MBH mechanism is not the inaccuracy of the predictions. Rather, it is the absence of any particular prediction at all.
--R. Erik Plata and Daniel A. Singleton, A Case Study of the Mechanism of Alcohol-Mediated Morita Baylis-Hillman Reactions. The Importance of Experimental Observations.