It's a 12-country trade pact that accounts for 40 per cent of world GDP, but what does it mean for Australia? Rarely has there been such a triumph of image over substance; rarely such an outpouring of admiration for a deal, whose details yet remain a secret, as there has been this week in the wake of the Trans-Pacific Partnership free trade announcement. "A gigantic foundation stone for our future prosperity," gushed the PM as business groups pumped out their press releases with zeal.