By Andy Silvester Those strategists who cooked up the idea of launching the Conservative manifesto at a Formula One venue no doubt had visions of Rishi Sunak putting some forward momentum in his campaign. Unfortunately for him, the whole event begged one question: has the Prime Minister got the drive to survive? The manifesto itself is a hodge podge of sensible ideas (the abolition of national insurance, a smart little tax break for landlords to sell homes to tenants without getting hit by capital gains) and ‘popular’ policies that do not bear up particularly well to scrutiny of even the most …