Standing on the 43rd floor of the Leadenhall Building one of the few still available to let - with British Land’s Tim Roberts and Chris Carter Keall of Oxford Properties, the 50:50 joint venture which has turned architect Rogers Stirk Harbour + Partners’ scribbles into a reality and one of London’s landmark buildings, it seems a very long time since the difficult decision was taken to mothball the site during the teeth of the global financial crisis in 2008.