OK being brutally honest here from what I've seen on the boards in the last 7 years.
I think *generally* they are a breed with guarding tendencies - I have no idea why but it seems to be one of the biggest reasons why cockers are re-homed, and one of the most posted about topics on the behaviour board.
I have a tendency to agree - I think part of it comes down to the Cocker's tendency to pick up things.... where this is misunderstood by new owners it can contribute to guarding behaviour.
I've often thought this as well with a tendency for some owners to grab stuff back off them thus the dog equally wants 'their' stuff back even more!
That was definately what I was getting at...
Honey is more of a guarder to other dogs, but I can see character traits in her that could easily escalate into guarding to humans if she had been handled differently. I suspect there are a lot of dogs out there in a similar position - and the advice of some dog "experts" to take things away all the time (without clarifying HOW - ie gently, making sure they are comfortable doing to, praise, returning, swapping etc) - likewise people pulling dogs off a sofa rather than training them to get off - can easily trigger this character tendency into problem guarding. There are also undoubtedly some dogs, like Archie, who are just prone to guarding by character without needing that "trigger"... and, I expect, these are the dogs who are more likely to guard random things like spaces - and I doubt this character trait is more common in Cockers (though I'm only guessing on that, as I have nothing to support it!). Perhaps this is a combination of breeding issues and modern day life stresses on dogs at play.
At puppy classes I have seen owners create guarding issues in their handling of their pups - and despite warnings at the beginning of the course that what they are doing could cause problems, they've continued and, by the end of the course, are asking how to solve the problem they've created...
- and that isn't limited to Cockers.
I guess the only real way to know if problem guarding is more of an issue would be to ask a wide range of behaviourists whether they see one breed more than another - and then compare this with the popularity of that breed...
I would say, Honey has always had her one special toy, that she seeks out to greet people with - she's never guarded it, but it is a definate favourite that I wouldn't dream of taking off her... it's something that gives her security and comfort.