You see, the big boss of DevTeach, Jean-René Roy, opened the beer cooler for the whole crowd in mid-afternoon. You can imagine that such generosity might influence the business-like atmosphere of the day's remaining sessions.
While Beth was demonstrating LINQ, she had uncharacteristic trouble with the Aggregation syntax... until she discovered that the From keyword was getting in the way.
What do you blame when your demonstration is hitting glitches? "That beer," she said, pointing to the bottle of suds near her laptop. "It's calling to me and distracting me."
When one member of the audience invited Beth to "Have some more beer!", Beth insisted, "I've only drank down to the neck." I believed Beth, even after she punctuated her presentation with 'crowd roar' sound effects close in on the microphone.
BTW, Beth did raise a valid aside during the LINQ to XML part of the talk: Why does Internet Explorer consider an XML file worthy of a security warning?