The kind of testing you did was more about size than personality. The Yorkie is a terrier and terriers come with a whole set of challenges of their own. Yes, most of us love our Yorkies but we have been visited by many people who were not loving the Yorkie experience. In many cities the Yorkie ends up in shelters and rescues quite frequently. They are not for everyone. Certainly not the easiest breed to train. I have had dogs all my life and just about met my match when I got Gracie. She was a little spit fire of a pill as a puppy and although she was the cutest thing on earth she was a stubborn little thing. I had to reassess all my training experiences and redo my approach with this one.
Go to the YTCA website and read about the history and personality. YT also has a good library that I suggest you look into. These are adorable little dogs but they are a lot of work and quite expensive to keep. It's all worth while if you have the kind of personality that will put up with a dog running your life. I think I trained Gracie pretty well but I still have days when I am quite sure she actually trained me.
Yorkshire Terrier Club of America