I keep thinking there is still more to this than is being reported. It is a "FADEC" control. For those of you who may not know, on a turboprop, the FADEC will adjust the prop to hold a constant speed, then adjust the turbine to hold the desired output torque (and the FADEC measures the torque on the output shaft directly - at least on the turboprop I worked on many moons ago it measured the shaft twist to determine the output torque).
The turboprop I'm most familiar with did not maintain constant torque, it maintained constant TIT. Trying to maintain constant torque at a constant prop RPM while in a climb resulted in overtemps, so the TIT became the controlled parameter.