The European Central Bank has opened the door to emergency support for the Spanish and Italian bond markets, setting off a blistering rally on bourses across the world. Picking codewords instantly understood by traders, Mr Draghi said the violent spike in bond yields in recent days was hampering "the functioning of the monetary policy transmission channels" - the exact expression used to jusfify each of the ECB's previous market interventions. Yields on Spanish two-year debt plunged 72 basis points to 5.47pc in barely an hour, with comparable moves on Italian debt - easing the pressure before a string of debt...