Great article. It describes exactly what happened with my first sheltie - a Jan baby. Really cold and snowy in Alberta Canada where we lived at the time, so we paper trained her. It really took only about a week for her to be completely accident free- but when it came time to go outdoors I had to provide paper and just like the article says gradually keep making it smaller. That process took quite a few weeks before she decided outside on the grass was okay too. She rarely ever would go while on a walk unless I carried a very small piece of paper - this lasted for many months. Usually she'd do her thing in her corner of the yard soon as we got back from a walk.
This is why I decided to use a crate and train Hanna to go outdoors right from the get go. So far she's doing great ( but I have some work to do on me) - her breeder used wood chips in a doggie pen and we have a lot of wood mulch around. So if I take her out she goes pretty quickly. She's had about 6 accidents in the house in the 5 days I've had her - all of which were my fault for giving her too much freedom too soon, and also for thinking that just because she just went she should be good for a couple of hours. Not always true.