I had put well over a thousand rounds through my Bisley Hunter before I sent it off for work and there was no real improvement.

I was also using a lighter return spring which did make the trigger lighter, but actually made the creep feel worse and more gritty. You could feel the roughness of the sear/hammer interface more with the lighter spring.

I now use the next stiffer return spring (40 oz vs 30 oz) after the work was done because it better suits me with the creep removed.