I agree with what everyone has said so far, my 3 are all used for working (or in the little one's case being trained for it) and take part in the odd working test and scurries etc. but they are also pets. I stand somewhere to the side of your breeder's view in that I don't think that working Cockers should be bred and sold purely as pets and I do think they thrive in a certain lifestyle but I don't believe that they have to be kept outside in kennels and never get to play or run around with other dogs etc.
I have to be honest though and say that if you are really serious about training a dog to a high level, either to be a top level working dog or most definitely a field trial/competition dog then you do have to limit their freedom somewhat, especially while they are being trained. I am training 8 month old Caoimhe to hopefully compete (although it's very difficult to get into) and she doesn't get to walk with the other two dogs, all her training is separate and she doesn't get to run around and do whatever she likes when we're out as if they get into the habit of free hunting for themselves and going too far from you it's hard to break; unless she's retrieving something the furthest she goes from me is about 7 yards. She gets plenty of play though and we have a massive garden in which she gets to play with the other dogs every day although under supervision. I never throw things for the other dogs when she's around or let her randomly run around after toys, retreives must always be done on command and returned to hand and it goes without saying that she has
never had the opportunity to chase birds, rabbits etc. I don't play tug games with her at this stage either.
Once their training gets to a certain level though then I can be much more relaxed, I did all the above with Rodaidh as well but once I was happy that his training had reached an established level he could go on big group walks, play fetch for fun, play tug with certain toys etc. because he knows the difference in play and working. Obviously I still maintain his training and he has a training session pretty much every day, as does Tilly, sometimes I train them together and sometimes separately and there are some things I just never let them do - bog off hunting on their own, chase any birds or game or ignore a stop whistle or recall being the main ones. If however you're only going to do the odd shoot here and there with your dog then you don't have to be quite so exacting, obviously though they still have to be trained to a certain level and know what to do and what not to do or you'll struggle to get invited back to many shoots
There are a lot of outdated views out there on training methods as has been said but using harsh or intimidating methods is absolutely not necessary when training dogs to work. I am firm with my dogs and I do expect them to listen to me and do as I ask but I do it with kind motivation - treats in the very early stages and always the '3 P' approach of praise, petting and play which are the motivators that they work for. The motivators are different for each dog; for Tilly getting to retrieve something is her highest motivation, for Rodaidh a chest rub and some excited praise are what really get him going. Go along to a few training classes and see what you think of them and speak to a few local dog owners and see if there are any they recommend or don't recommend and try the Gundog Club, they run training classes in most areas and have a system of graded tests which are fun to do.
