We were waiting for the magic moment to happen. When Paulie settled in and started being a senior dog in retirement. Right when we thought that was happening, Paulie changed course and we were starting all over again. It takes a lot of patience to handle a reactive dog and be quick on your feet to respond. Since I was home, (pre-pandemic) most of the time and taking online college courses, the only time Paulie would be calm is when he was in his crate, (door open) with me in the office. As soon as I got up to walk across the room, he would leave the crate and follow me. This went on all day and I don't know about him, however, I was exhausted watching him. From time to time, I would sit on the floor by the crate and sing my "puppy dog", song that I made up. During this time, he still had his hearing and eyesight and sense of smell was 100% intact. Also, he was very fast and slick when he would run to the front door. He was always on edge, afraid something would happen to me. Much later, I heard the term, "velcro dog," and by all means, he was exactly that.
Early on, we allowed him to join us on the chaise/sofa as he slept by us. I bought those doggie stairs since he was a low rider, as he had trouble jumping up. What we found was when we left the house then came back in for something, he had no issues jumping up! "Busted!" we would call out and see looked to embarrassed. One of the trainers taught us how to train him not to lay on furniture and Paulie learned quickly. Afterwards, he slept on his bed on the living room and bedroom floor. When we thought he was sound asleep, we observed that his ears would always be honing in on the sounds in the house. I even tried tippy toeing out of the room and when I turned around he was there.
Another situation would be if anyone rang the doorbell or if we contractors come to do work. We had to put on his leash and walk him to the door to meet the person. If he was in a room with the door shut, it wasn't a pretty scene. After sniffing the person would determine if they were good with Paulie. If not, Paulie would show his teeth and growl and bark. Then we had to take him into another room and babysit him. So, to answer my topic question, it depends on the dog, his age, and how good the trainer is to break this reactive cycle. This is just my opinion based off our experience. I'm convinced that if someone else had adopted Paulie and didn't have the time or patience, Paulie would have been returned to the shelter. For us, once you sign the adoption contract, you are in it for good and bad. Looking back, we don't regret adopting him and thank God everyday for giving us that opportunity.