I'd simply reply that if he thinks no candidate before didn't choose themes that people were concerned about and didn't know that you had to speak to emotions, he wasn't watching. He's telling us that, before, we had politicians lining up policy and programmes and being dead serious? Then how did Chirac get elected? Mitterand had a programme - was forced to have a programme - but he knew that wasn't what would make people vote for him.
It may be that Royal and Sarkozy play the media more than any pols before them. But they're fifty-year-olds, not eighty-year-olds. The media take up a different place in life than they did a generation ago. Alain Duhamel should know, he's been in and out of newspapers, magazines, and TV studios for thirty-odd years.
(Nitpick: Ils savent pourtant l'un et l'autre... means "They both know...")
Strangely enough, the Fifth Republic was founded by someone who was pretty much down with that...