Why can't I make a good canned demo?

I am a pretty fabulous demo artist. Give me a live audience or even over the phone via GoToMeeting and it's smooth sailing for the next 30 minutes. So why am I always struggling with creating a canned demo to post on the website?

In live demos I work with an outline, rather than a script. When I stick to the outline for the recorded demo, I find myself stumbling, stuttering and reaching for words that flow easily with a live or virtual audience. When I try to follow a script, it only gets worse.

I suspect it's the unnatural feeling of talking into the void with no feedback of any kind. I may also be a lot harder on the results when creating a recorded demo, which can be re-edited to perfection and my audience knows it.

After doing some Googling, I also think I may just be doing it wrong. In the past, I have set out to essentially capture what I do in a live demo for on demand viewing. But that's not really what users expect. And likely my own experiences evaluating software color my satisfaction with my own work. Though relatively ancient, this case study [PDF] makes some great points, particularly about brevity, focus and navigation. Most of what's outdated or irrelevant is due to the fact that we can all make great demos for well under $50,000 using better and cheaper technologies. Even better, though, was this TechRepublic webinar, which presented a specific strategy for creating brief, focused and just plain awesome demos. I'm going to put it in practice and see if I get any better results.