It was, Angela Merkel reflects, the most galling mistake of her childhood. Not a lie or a betrayal, some malicious gossip or a fistfight but the moment in which the young girl from East Germany crawled into the resinous hollow of a tree wearing a new tracksuit sent to her from the West.

The anecdote speaks volumes about a dutiful, conscientious, slightly awkward woman who, though pre-eminent in Germany for seven years, is still a relative enigma to her compatriots. It was a response to an array of questions put to her by Süddeutsche magazine as part of a broader inquiry: "Who is this person who is governing our country?"

The answer: a woman who regrets not being able to go shopping without being recognised; who would most like to have supper with Vicente del Bosque, the manager of the Spanish football team; who powers down through hiking, cooking or laughing and whose biggest fear is, no, not the collapse of the euro, but getting caught unprotected in a thunderstorm.

A man who knows Merkel better than most and admits to being referred to as her "little pet" is David McAllister, 41, an up-and-coming member of the Christian Democratic Union (CDU) and prime minister of Lower Saxony who has been tipped as a future chancellor (and also happens to be half Scottish). He puts her success down to her commonality. "There's no ballyhoo with her," he says. "She's very direct and down to earth. What Germans love is they see her on Friday in Brussels with Hollande, Obama, Cameron, whoever, and then they see in their newspaper the next day how directly after that she went shopping for her supper in the supermarket. The photograph of that wasn't fixed. Everyone knows that that's the way she is."

He also credits her with modernising the CDU, a party whose members – typically Catholic, male, western, family-oriented – she has led as a Lutheran, eastern, childless woman. "I think there are hundreds of thousands of people in this country who now vote for the CDU who wouldn't have done before her," McAllister added. He said that while well aware that Germans tend to vote for a party rather than a personality, the CDU is desperately trying to persuade people "if you want Angela Merkel you've got to vote for the CDU," in recognition of how strong the Merkel factor is.

Others are less charitable. The academic and former adviser to Helmut Kohl Gertrud Höhler, describes her as furtive, dangerous and a threat to Europe in her new book, The Godmother: How Angela Merkel Is Reshaping Germany, in which she coins the phrase "System M" to describe Merkel's modus operandi. "For years, the press has concentrated on the question as to whether she governs well, or badly, or perhaps not at all," said Höhler. "In reality, Merkel has developed an autocratic system," she said, and has "already installed an autocratic regime".

She accuses Merkel of ruining the euro and undermining the political careers of many leading men in the CDU. She even mentions her in the same breath as German dictators of the last century and goes so far as to suggest her strict Lutheran pastor father's decision to bring her up in the authoritarian confines of the communist East, where Merkel moved with her family when she was just weeks old, was an extension of his deep desire to control her. But Höhler's book cuts against the grain of popular opinion, which still strongly favours Merkel. According to the latest poll her popularity rating is 61%, making her Germany's most popular politician.

Wolfgang Nowak, director of Deutsche Bank's Alfred Herrhausen Society and a former adviser to the SPD chancellor Gerhard Schröder said the reason many people, including Höhler, were suspicious of Merkel was precisely because she kept so much to herself. "The reason there's a System M is because it's the first time in German politics that a chancellor's office sticks so tightly together so that nothing is leaked. Merkel talks to just a very small, tight, trusted circle and those who are not in that circle are often envious or offended," he said.

"There's also the theory," said Constanze Stelzenmüller of the German Marshall Fund "that Merkel is the kind of person that decides the more you say and the more you write, the more these things can be held against you and the less said the better, the more done the better. I'd guess her motto was: 'Let's get more done' and that strikes me as entirely sensible. Particularly in a media age, that's a sign of strength."

Nowak added it is indeed true, as Hohler writes, that many men who once held big positions in the party are now gone, "but not because Merkel killed them off, rather, they were simply unmasked for what they were – CDU career politicians, puppets or fraudsters".

Gunnar Beck, a reader in law from the University of London's School of Oriental and African Studies, is rather more sceptical, saying that Merkel is only held in such high regard because those around her don't make the grade. He is critical of her diplomatic skills, as well as her judgment of character. "By comparison to a rather unfortunate line of politicians who have been exposed for irregularities of various kinds, (including the former president and former defence minister) she appears to be the paragon of virtue and that's noticed by the electorate, albeit in the context of a low general standard. She's entirely above criticism in her personal life and work ethic, but you've got to put it into perspective. While she's a very good domestic political operator she is helpless abroad and she's also a spectacularly bad judge of character," he says, citing her promotion of many who have since fallen (including the president, defence minister and Nicolas Sarkozy) and others who have not, including the European Central Bank's president, Mario Draghi, and Jorg Asmussen, an executive board member of the ECB. Beck is also wary of the idea that Merkel has a sophisticated plan. "She is a superbly shrewd party and domestic politician but has been repeatedly outmanoeuvred by Draghi, Monti, Hollande and others. There is no sign that she has a masterplan regarding the euro."

Among those critical of Merkel's lack of vision is Hans Kundnani, a Germany analyst and editorial director at the European Council on Foreign Relations. "What's needed now is someone who can talk up the benefits of the single currency, of Germany's role in the euro narrative, including the fact that it bears responsibility for this flawed currency, rather than saying: 'we're the victims of it,'" he said. "She's not particularly visionary or bold."

Gerd Languth, a political analyst and Merkel biographer, said this was precisely what Germans liked about her. "She is extremely pragmatic, and non-ideological, like most Germans are." She had, he said, been strengthened by the knowledge that despite criticism from outside Germany over her euro policies, the support for her within was stronger than ever. "She notices that the more she's attacked from outside, the more the solidarity towards her within Germany grows," he said. "Germans don't know what she wants, but the trust in her is unshakeable, and if the ship cants, she's the one they want to be at the helm."

While there is at this stage, a year before a general election, quite a degree of expectation that Merkel will be re-elected, much is still at stake, not least, if the German economy takes a dive or the euro plunges into more misery, which could see the tide of popular opinion turning against her. Despite the growing disgruntlement towards her among Christian Democrats, Languth said he found it hard "to imagine a CDU governing without Merkel if they're standing high in the polls".

What he is sure about though is that if Merkel were not re-elected "she'd disappear from politics altogether". Asked what he thought she would do, he said that unlike her predecessor and close friend of Putin, Gerhard Schröder, "she would not go to work for Gazprom".

The final paragraph of this article was changed on Thursday, September 20 to read "close friend" of Putin rather than "close fiend". The error was introduced during the editing process