here is the thing fishhead...

Because of the extremely low survival rates of the progeny of hatchery fish in the wild there is no change in the genetic structure of the native fish.

I am not trying to debunk the study at all. What I am saying is that the hatchery fish don't influence the gene pool because the progeny of the hatchery fish do not return as unmarked adults. The do not return at all.
The problem with hatchery is when a hatchery fish spawns with a wild fish thereby eliminating the wild fish by making it unable to reproduce.

let me know if I am not being clear enough