Just what we all needed: another Ben and Jen who don't know enough to keep their courtship ups and downs to themselves. The boardroom-minted Stiller/Aniston team turns its questionable talents to the story of a risk-assessment analyst looking to love again after a disastrous honeymoon, and the uninhibited party girl he ends up falling for. Somewhere within this premise lurks the potential for an amiable romantic comedy about the pitfalls of calculation, but that's not the direction filmmaker John Hamburg (a co-writer of "Meet the Parents" and "Zoolander") chooses to pursue. Instead, he opts for industry-standard pratfalls and poo-poo jokes -- that is, when he even bothers to give one of his credulity-straining setups an actual payoff. Just as often, scenes sputter to an ignominious halt. It's not as if the movie can get by on personality: Neither of the lead characters is even partially endearing, leaving it up to co-star Philip Seymour Hoffman (who plays Stiller's buddy, a washed-up child actor) to save the day. But know what? Even his ability to spruce up a dog of a script with method eccentricity is losing its potency.