Sir Stuart Rose held a gun to the head of the Marks & Spencer board, and won. The awkward choice facing his fellow directors was, either accept a super-powerful Rose or no Rose at all. M&S chairman Lord Burns judged that a rose by any other name would not smell as sweet, and capitulated.

Sir Stuart therefore combines the role of chairman and chief executive for the next three years and for the leader of a listed blue chip wields an unprecedented amount of power.

That may not necessarily be a bad thing. His elevation provides continuity. It allows him to go on with what he has plainly not finished: the rehabilitation of M&S is still a work in progress. It gives the company breathing space to identify and groom the next generation of leaders. And it ensures M&S still retains the undoubted talents of an energetic and charismatic leader.

But there are risks. A lot of power is concentrated in one man's hands. The extra responsibilities of Ian Dyson, the finance director, look like a sop. He has not even been given the job title of chief operating officer and, bluntly, has been a numbers man with no operational experience all his life. Sir Stuart is surrounded with his own appointees. Six of the older guard, who might have provided some counterweight, were pushed out yesterday.

In the boardroom, Sir Stuart is also dominant. Sir David Michels, the senior non-executive director, is no pushover, and another non-exec is to be appointed, but given Sir Stuart's dominant personality, they will have to work hard to prevent an autocratic tone entering M&S culture.

That dominance has been a force for good in the past three years. Sir Stuart has restored self-belief at

M&S and quickly put a stop to some of the duffest decision-making in the FTSE 100. Shareholders have not forgotten the dotty decision of the previous management to try to sell expensive minimalist furniture in Gateshead or to advertise using tubby models.

But it may not be the right approach going forward. There are already doubts about Sir Stuart's formula, as evidenced by the lacklustre recent sales perfomance. The M&S share price is almost exactly back to where it was when he joined the company three years ago, though some of that can be blamed on general economic worries.

And there may be residual concerns about Sir Stuart's judgment. This was a man who thought there was nothing iffy about piling into M&S shares ahead of Philip Green's takeover approach. Mind you, the Financial Services Authority agreed.

Sir Stuart's alpha personality type - while ideal for motivating backsliding shop workers and impressing City analysts - is just the sort that might benefit from the curbing influence of a sagacious and independent chairman.

M&S claims that it consulted its largest shareholders and they were “broadly favourable”. Yet within hours of the announcement, both Legal & General and the Association of British Insurers were sounding off about the appointment.

The revolt looks too little and too late. The time to protest was before M&S went public. A rebellion now might do serious damage to the company and distract it at a time when it needs to be on its mettle.

M&S's predicament should be a warning to every public company that succession planning needs to be permanently on the agenda. Not to have a “Plan B” when negotiating with a well-ensconced chief executive is a recipe for trouble.

patrick.hosking@thetimes.co.uk

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