GASEOUS FUEL ENGINE SYSTEM OPERATING STRATEGY INCLUDING HYDROGEN FUELING AMOUNT BASED ON PERFORMANCE TARGET

Operating a gaseous fuel engine system includes outputting control commands to a first fuel admission valve and a second fuel admission valve to admit, respectively, a gaseous fuel blend containing a gaseous hydrogen fuel (H2), and additional H2, into a gaseous fuel engine. An amount of the additional H2 is determined by way of the respective control command based on a performance target for an engine parameter varying on the basis of a relative amount of H2 in a combustion charge. Related apparatus and control logic is also disclosed.