I found the secret with my dogs about their bathroom habits a couple of years ago and it still amazes me every time I go to clean up the yard.
After having a litter of puppies and finally being down to two, Zappa and Fiona, plus Brut and Silver, I was just grateful they were going outside that I didn't care much where they did it. I also wasn't making any special trips in the middle of a snowstorm at odd hours of the night to teach them to use a particular area of the back of the yard and so I was left with a mine field to clean up.
I was stumped at how to retrain the dogs to use certain areas of the yard. Especially the older dogs. I didn't see much success with them. When the puppies were a year old, I was raking leaves and we had a burn ban because it was so dry, so I left the piles to sit until I could take care of them. When I went out to clean up the yard the next day, low and behold, they were using the leaf piles. A light bulb went off. So I arranged the piles at their favorite spots and they continued to use them. The first year was about an 80% success rate and by the second year is was more like 90%. Now I would say I can count on knowing where to walk in our yard. I couldn't figure out how in the world I could retrain them and they did it for me! It still blows my mind when I do my yard duty that I didn't have to do anything, they did it on their own. I don't have to do anything but rake the leaves from the fall into the same piles. Fantastic!!
I have no idea if this would work for other dogs or not, heck, I still don't know how it worked for my dogs, but the whole thing has been a life saver and it even works in the winter. That is just so cool!! It is equally great that we have a yard full of trees, which means endless leaves , and a forest floor, so there is no lawn or grass to kill. Somebody up there was listening, because this was one thing I could never do on my own! Isn't it simply amazing how things just work themselves out?