He wasn't ad-libbing. A network or remote service being unavailable is a common occurrence in presentations. I can't say I have a scripted response for every

He wasn't ad-libbing. A network or remote service being unavailable is a common occurrence in presentations. I can't say I have a scripted response for every common contingency, but I'm not Steve Jobs. If he's a rehearsal freak, I'm sure he rehearsed the common problems and didn't just repeat the ideal case over and over again.