In your other thread you said he was still taking some medicine and you still need to go back to the vet. Personally I would wait for a clean bill of health from the vet before I rule out that his problem being medical. He sounds like you've done a good job getting him to let you know when he needs to go. During the day, I would just wait for him to tell you he needs to go rather than asking him. Other than that, I would discuss what he's doing with the vet on your next visit and let them tell you it's not being caused by his medical condition. You don't want to untrain a good thing.
Sandy, Koke and Lelaska's Mom