Banking boards are under intense scrutiny for being too weak. But Barclays has a different problem. Its board is overflowing with strong characters.

The issue has returned to the agenda following the resignation of Paul Idzik, the bank’s chief operating officer. He is leaving mainly because Barclays failed in its bid to buy ABN Amro – a deal he would have had an important role in integrating. But his impending departure has also revived longstanding concern about Barclays’ boardroom politics. Mr Idzik has been a key intermediary in the mysterious relationship between John Varley, the chief executive, and Bob Diamond, who heads Barclays’ investment bank.