Stocked birds do not dilute the population because they don't live long enough to do it. They have zero natural escapability or survival instincts.
Anyone who thinks that chasing flair nares is similar to hunting wild birds needs their head examined.
Clearly there are two factors that improve wild upland bird populations: 1) habitat, and 2) weather. Planting pseudos does nothing to aid populations.
That being said, they are very good at serving one purpose: training a young dog because they are dumb and guarantee success.