Effective combustion modeling relies on the precise estimation of hydrogenair combustion characteristics. In this sense, Millán-Merino and Boivin [1] designed a single-step mechanism for hydrogen combustion that accurately recovers the adiabatic flame temperature using a variable stoichiometric coefficient formalism. The present study proposes a drastic simplification of this approach (further reducing computational cost and complexity) and formally clarifies the contribution of the variable stoichiometric coefficients and their evolution across the flame internal structure.