Well Tim I don't so much think it's stubbornness as it is them trying to figure out how it benefits them my bully isn't so much food driven as he is praise driven he LOVES hearing he is a good boy but a great deal of bullies ARE food motivated find that much covered treat and use that as a training tool. First and foremost you have to make sure your bully knows where it stands in the pack order a bully that knows his place is a comfy bully. Bullies are very social and love being with family so as a discipline you can put them in another room for a short period as a" time out". Generally though yes patience and perseverance are key in training a bully.
Bulldogs rule...cats drool..."the Shelly Bean"