Slow Leadership has a great post on the limits of leadership techniques.
One big limit: If the technique does not fit the person, it won't last. The person must be before the person can do. Many people go to workshops, get pumped up on some technique, go back and try it for a few days, and then revert to their old approach because although the technique was new, they weren't.
Another key point: You learn to lead by leading. Books and training are helpful in identifying things to avoid but the actual practice of leadership must be acquired by practicing leadership.