It seems you may have "summed it up" without any thought about the consequences. In a country that seems to have "diificulty" counting hours and cycles maybe you should have asked your maintenance engineer "Why?".
Apart from the possible financial implications it has a lot to do with the design of the engine..
The catch is the injection wheel. This wheel is subject to considerable thermal cycle fatigue. If it fails, most of the gas generator rotating assembly will leave the engine rapidly. It has been proven a few times, so don't bother.
There are units which will record what you want - 1 is a tacho box from Turbomeca and there are a few aftermarket units. Or is this a case of "can't be arsed?"