I'm of the minority opinion that, in general, a return spring cannot drop poundage, a trigger bar cannot mate, a firing pin block/spring cannot mate, and a sear cannot mate on a clean firearm and produce a true trigger weight reduction.
I do believe a person gets used to a trigger over time and attribute that familiarity to "improvement."
One lbs drop by mating? Unlikely. 1 lbs drop in spring tension? That's an interesting position. Grittiness cleaned up, possible.
Not helpful to your specific model, but the concept in general of weight reduction just by firing is always questionable in my mind. I haven't experienced but have good collection?