LONDON (AP).- Security chiefs complain intelligence is often sketchy — and here’s the proof. Artist James Hart Dyke on Monday unveiled a series of paintings and drawings completed during a rare 12-month study of Britain’s overseas spy agency MI6. Dyke, who has been a war artist with the British military in Iraq and Afghanistan, was granted access to secretive sites at home and overseas. The project was sanctioned as part of events to mark the service’s centenary in 2009. Last year, historian Keith Jeffery published an official history of the agency’s first 40 years. MI6 chief John Sawers said last year that the commemorations would be a rare opening up. He said spy agencies must “stay secret, even if we present