Austin - "How many of you own a rooftop voltaic system?" Mr Bush asked the crowd in Austin, Texas. The Republican presidential candidate was trying to use irony to show up the complexity and narrow focus of some of Vice-President Gore's proposed tax cuts, but forgot one small detail. Mr Bush's own energy policy statement offers voters precisely the same $2,000 tax credit for home-owners who decide to harness energy from the sun. Ooops!