I rehomed Laddie, shorthaired pointer, 9 years ago at the age of 5 - he had never been trained or apparently let loose in a field, but he knew to flush, quarter, retrieve, present by instinct with just little encouragement (he hardly ever pointed though) He was small for the breed so I assumed he came from a working strain. He followed scents obsessively, and with huge enjoyment. I`ve now rehomed Shamus, shorthair aged 2. He is much bigger, and very handsome and also not trained beyond Sit and Down. His behaviour echoes Laddie`s BUT without the drive. He`s lovely, and beginning to play and take treats so I can start training him, but I wondered if he was maybe bred from a pet / show line? Is there such a thing with GSP`s?
I think most lines are pretty dual purpose but even in working lines of breeds with a clear divide some are workier than others and some have zero instinct!
There are those who are bred by working kennels, specifically for the working community and I suppose there are those who breed them, show them but dont actually work them. Like Muddiwarx said, I think most lines are either/or and there isnt the kind of clear divide you see with Cockers for example.