To benchmark the suitability of a given descriptor x as a trigger for enhancing/diminishing Z-E isomerization by photoexcitation, we elucidate its performance in predicting the 'mathematical reaction coordinate' p(S1→S0-E,x). The latter refers to the above-described statistics of p(S1→S0-E) -which was devised as a function of x, that is the value of the given descriptor at the instant of the electronic decay S1→S0 (implemented by switching of the MM models). This target function is approximated by a sigmoid-type fit function p(x) according to: