At 66, Mr Kiley could be forgiven for abandoning a job where he suffers constant frustration at being denied the sort of untrammelled power he took for granted in similar posts in the US. He is also, say colleagues, doubtful he can deliver major improvements within the funding straitjacket ruthlessly imposed on the Tube by Chancellor Gordon Brown - at least, not enough to safeguard his reputation, brilliantly acquired running New York's subway, as a miracle worker.