I noticed a funny messup by James Cagney in the "Preparing for CCNA Cisco IOS Commands STP_Protocols" video (
http://tools.cisco.com/cmn/jsp/index.jsp?id=56243&redir=YES&userid=(none))
At 15:50, he says, "So its DLCI, Data Link....CI [awkward pause]"
He obviously forgot what CI stood for on the spot. It's fun to see the Cisco experts forget simple things like us too!