I've watched a number of demos, and done a few myself (I'm not trying to do anything now, I need more skill building technique).
I think entertainment value is important, you need to hold the audience's attention.
From the beginning, I went to intermediate and advanced demos, I figured the beginning stuff was "self explanatory" (I was VERY WRONG) A well considered and "intuitive" program is important to keep your audience on track, and (IMO) it has to be done in a way that is interesting to the intermediate and advanced turner, but accessible to the beginners... I say this, because as a beginner, I thought I could take in a lot (and I could), but the information didn't transfer to the hands. I understood, but couldn't duplicate and I sometimes put myself at risk. I'm getting better at that.
Till us

"super turners"

figure out that we are just like everyone else, and need to learn the basics, just like everyone else, I think that basic techniques and SAFETY should be a pronounced part of any skill building demo.
That said, At the first symposium I ever attended - before I had turned anything, Keith Tompkins did a segmenting demo (the first one he ever did, I am told) that had no actual turning in it, but was interesting, amusing, informative, accessible and doable... I STILL have not used the technique for segmenting yet, but his demo lead me to try building a sled of my own design (that works really well for it's purpose) and given me ideas about and methods of examining my own ideas that I will always use.
I'm going back to school myself to insure that I can use and show basic skill and safety, before I try another demo, I want to be as good and as safe as Don Orr and/or Paul Petrie (and a whole lot of the other guys I have learned from in my club).