The other side of the double edge problem with punishment is that there is always fallout with any form of punishment–even something as benign as a time out. The more punishment you use in your training the more anxiety you create for the dog. You won’t always know where or when but it will express itself somewhere else in the dog’s behaviour or performance. Yes I use punishment, negative punishment but I try to keep the application of (mostly in the form of a manipulating response cost or applying time outs) to no more than 15% of my training. Even if the dog’s tolerate it, there is still a double edge problem with the use of positive punishment. First of all, there are so few trainers out that have such phenomenal timing, they do exist because I have seen them in action, however there are rare. So when people with poorer timing try to reproduce the punitive methods the resultant dogs work with in fear hence the stress response, cowering or tail tucking.