Andrew Mixergy - How your mistake made me remember a plug

I recently watched a rather excellent interview on Mixergy (http://mixergy.com/nick-oneill-allfacebook-interview/) and the entire interview is actually filled with nuggets of gold, but I wanted to highlight one really important thing that might not be so obvious: At the tail end of the interview, Andrew went to do a plug for one of his advertisers/sponsors, and it involved a testimonial he received via email from a customer. Turns out, he couldn't pronounce the customers name. Ironically, Nick knew the person and helped out. Anyway, I am almost blind to any form of advertising and pretty much just block it out. But because of the way this unfolded, a day later I still remember the persons name (Guarav) and I remember the product being pushed. And...I actually ENJOYED the plug! Andrew was embarrassed, but should not have been! It was just so authentic, a little humorous and not at all a negative reflection on Andrew (i.e. lack of prep, etc...).

This made me reflect a little on my own experience. I'm often discussing and demonstrating complex technical tasks in front of prospects/customers as part of my job. I long ago gave up trying to have the perfect script, flawless demo and decided instead it was better to just roll with the punches. This creates a situation where things are not always perfect and mistakes happen, but that inevitably happens with the perfectly scripted demo too! But interestingly, when mistakes do happen, the audience becomes MORE engaged and I think they remember things better. I'm thinking it must be the result of the same thing I experienced with Andrew's interview. This isn't to say a drastic mistake will not leave a negative impression, but I'm wondering if minor mistakes are actually a net positive??

Do you have examples of where mistakes/imperfect interviews/demos/etc... have worked out favorably for you?