I think with cockers the problem was
Lady and the Tramp. No--seriously!
They became a fad breed to own, which opened them up to overbreeding and bad breeding. There was
demand for a cocker, any cocker, and no regard for their original purpose. And as long as the public didn't care about the breed other than as a cute lap dog, the instincts that had been part and parcel of the breed were nearly lost. And because of bad breeding lots of problems cropped up in cockers.
Breeders who care about restoring the cocker to what it once was are making some headway, but it's going to be a long haul.
Having said that, bless you and your husband for wanting to help Lady refine her instinct even though she was not originally intended as a hunting dog. If she has the instinct, she'll be much happier if you can tap into it through some exercise, whether it be hunting or trials or even tracking.
Our dogs are bird dogs, too, btw, bred and trained to be close-range pointers for foot hunters. Half our dogs are from a breeder, half are rescues. Some hunt, some don't, though all were originally bred for hunting. Watching a dog follow scent is an exhilarating experience, and working as a team is something that just can't be duplicated. For us it's not about taking game but participating with the dogs, even if it's just a mutual walk in the woods. We love all of them whether they hunt or not.
With setters, the bench stock often have lost the instincts that made the breed good bird dogs. But it's possible to combine the beauty of bench with the instincts of good hunting lines and end up with a combination of both. Sometimes you end up with neither.
But we
have noticed that those of our dogs who
do hunt seem to have a joy in life that the nonhunters lack. Especially come fall.