He didn't have to see the match to give this comment. To me it's just a nice thing to say that he's happy for them, because he knew how much they wanted it.
And I think you can't compare Olympics to Davis Cup. It's a whole different event. In Davis Cup the conditions are different, the atmosphere is different. I wouldn't say the French can't beat the big teams, Llodra's record with several partners (including French ones) isn't too bad against the Bryans. And the Bryans are probably the only team which also plays in DC together, most others have partners from another country.