It’s been a tough autumn for US chief executives.  The bosses of two of Wall Street’s behemoths have been toppled and canny Dick Parsons at Time Warner had the good sense to formalise his long-flagged departure. Other, once imperial, titans are hanging on by their finger-tips.

The fall of the US’s corporate princes makes riveting drama  for the rest of us. But, over the past few weeks, I’ve also had several reminders of another transformation afoot in many of the country’s executive suites. Among the chiefs who still have their jobs, many seem to be rethinking what it means to be a boss and coming up with a model that moves a lot of power a lot further down their organisations.