Re: Best line today on debates
A good indicator that someone knows their stuff (applies to any field, not just politics) is that they can tune a response to an audience, re-word it into a different context, and come up with several ways to get the idea across. All of them consistent on content.
A person who has a solid set of political principles and knowledge can field unexpected questions, because it's simply a matter of applying the ideas and experience to a new situation. Note that this applies to any field of knowledge: an experienced workman can deal with a new repair problem because he knows his tools and knows his techniques.
You can't "rehearse" real knowledge, and Perry is far from the only politician who suffers from this.