Okay, the last time I called attention to the new-found twitch in President Bush's delivery, it was after the speech introducing now-Chief Justice John Roberts, and many commenters protested that the President was just suppressing laughter at the antics of Roberts' rambunctious son, present at the festivities. That, even though most people's attempts to avoid laughter don't involve a repetitive twitch.
Fine. In the intervening weeks, I've watched Bush speeches regularly, and the twitch has remained a constant, although not in extemporaneous appearances. Now, this week, in his press conference announcing the nomination of Harriet Miers, the President has broken through that barrier, and here is the video evidence. As far as we know, the unmarried Ms. Miers didn't bring her non-existent rambunctious son to tempt the President into laughter. Other explanations, of course, are welcome.