Business Opinion/John McManus: There was a very interesting article in the Financial Times last week. The author, Prof Sydney Finkelstein of the Tuck School of Business at Dartmouth, gave 15 warning signs that an executive was just about to screw up, or had already started.

By coincidence it was published on Wednesday, the day after Ryanair's first quarter results had generated a lot of chat about whether the airline's business model was not without flaws. In particular its focus on capacity growth at the expense of yields.

Applying Prof Finkelstein's 15 rules to Michael O'Leary, the Ryanair chief executive is most entertaining and quite enlightening. The rules come under four headings and we shall approach them in that order. The first heading is "ignoring change" and the tell-tale signs are:

The extent to which Mr O'Leary exhibits these traits is almost uncanny. He seems to be at a complete loss as to why Aer Lingus is still in business, never mind on track to make profits of €80 million this year. More seriously, he does seem to have focused on capacity growth at the expense of other elements of the business.

But the one I really like is the last one. Nobody who has seen or heard Mr O'Leary dealing with customer complaints on the radio and TV can fail to be impressed with the arguments he puts forward for things like cancelled planes, not paying compensation etc.

The second category is called "the wrong vision" and the things to watch out for are:

• You have always used the same approach - it has worked in the past and it will work again.
• You have your customers figured out. You have known what they wanted for years.
• You run your overseas business just as you run your domestic business. If it isn't broken, you don't fix it.

Now lets take a look at Mr O'Leary. He is almost messianic about the Ryanair approach and the travelling public's desire for low fares above all else. In addition he is almost a parody of himself at this stage when it comes to opening new bases in Europe. He turns up in the same tight-fitting rugby jersey, poses for the cameras and makes a few cracks about the national carrier. Behind the scene the model is the same, cheap airports that are out of town and lucrative deals with the airport operator and preferably the local government.

Next we look at the category called "Getting too close". Prof Finkelstein's warning signs are as follows:

• Your CEO appears to identify so completely with your company that there is no clear boundary between personal interests and corporate interests.
• Your CEO is devoting seemingly excessive time to fulfilling personal missions that do not necessarily benefit the company.
• Your CEO tends continually to reinvest in corporate initiatives that he or she favours, despite your company's inability to make those initiatives work.

At this stage you would have to wonder if Prof Finkelstein didn't have Mr O'Leary in mind when he wrote his article. Although only Ryanair insiders could judge how well he fulfils these criteria Mr O'Leary is Ryanair as far as the public is concerned. He is also obsessed about a second terminal at Dublin airport and the destruction of Aer Rianta. Two issues of relatively minor importance - you would have thought - for an airline that sees itself as European, rather than Irish operation. Again, you would wonder whether the whole Dublin airport saga does not come under the final criterion.

The next category of warning signs is "Arrogant attitudes"

• Your CEO believes that your company can do whatever it pleases because of its dominant position in the marketplace.
• Your CEO seems almost to show disrespect for competitors and suppliers.
• Your CEO elevates public relations considerations over strategic considerations.

Step forward and take a bow Mr O'Leary.

Lastly we have the "Old formulae" category:

• Your CEO makes the same decisions repeatedly, even when those decisions no longer seem appropriate.
• Your CEO tends to shut down lines of inquiry that markedly differ from his apparent preferences.
• Your CEO is unconcerned with all that could go wrong in his strategic initiatives.

Again only Ryanair insiders can accurately judge the extent to which Mr O'Leary fits this particularly bill. Publicly at least he is a stranger to doubt.

So is it time for Ryanair to dump Mr O'Leary? Depends whether you prefer the track record of one of the most successful businessmen in modern aviation or the theories of a US academic from an Ivy League school. Worth thinking about all the same.