Yet Tom Gallagher, an analyst at ISI Group, a broker-dealer, estimates that investors' expectations of yields in five years' time, when such temporary factors will have faded, are no higher than they were last summer.
Chief executive Craig Gallagher, who led the original management buyout of the company from engineering group Motherwell Bridge in 2007, will be chief executive of the enlarged business.
In the run up to the 1997 election and afterwards, Mr McGee - who discovered the group Oasis - attended a champagne reception with Oasis frontman Noel Gallagher at Downing Street.