I don't really see it as "blaming" the breed, there are differences among breeds, and some are harder to train. I took YorkieRoses comment to mean, if you've only owned one yorkie, you may not know the breed as well as you think. Most breeders are pretty much in agreement on Yorkies being more difficult to housebreak. Every now and then someone gets a yorkie who was a breeze to train, and they thnk because at 4 months old there have been no accidents they are out of the woods.
There are lots of individual difference between Yorkies, some take longer than others, even if the human is doing a good job. No doubt, Joey, took longer than my son's two Shih Tzu's and he trained them the way I trained Joey. If Joey started having accidents once a month, I would try to look at what's different? For example, Joey doesn't really like a dirty pee pad, and although we have two pee pads out for him, one in each of our offices, if we are both in an office and he has to poop, he'll go in the hall. I could put another pad in the hall, but I don't want to, the poop pretty easy to clean and it doesn't happen that much, but it really is my fault when he makes a mistake. I really think Joey wants his own room where we go to clean his pads, and don’t stay long. I don’t know why he’s such a private dog. Maybe he takes after me.
