But then I've come across some dogs that just wont listen and I've seen their owners struggle with them.
I've known many dog owners struggle, only to meet the guy who does our local training classes and see that their dog
does listen... It's just the owner that needs to speak the right language and convince the dog they mean it.
That's the key, IMO. You need to be good with dogs in general, in
that kind of way. You want them responding first time, every time, whether they're chasing rabbits, sniffing a hedge or especially having a crack at each other... and without any stupid Caesar Milan style tricks.
but that if I wanted to I could go away and learn more about different breeds of dogs to increase my understanding of their needs and personalities.
Good starting point, perhaps, but don't rely on it.
Those are only guidelines and even then more for Breed Standard showdogs. My three are fairly pure-breed of their various kinds (Border Collie, Welsh Collie, Black Working Lab), but in no way typical of personality, especially the Border Collie.
Without meaning to sound like I'm accusing you of 'doggie-racism', judge by the dog itself not by the breed and get to know them individually. We always swore we'd not get a Collie because of how mad the breed is always described - We ended up with two of them!