Como Mundungus convenceu a Ordem a usar o plano dos Sete Potters?

Mundungo é uma parte importante da Ordem.

‘How come he’s in the Order?’ Harry said, very quietly.

‘He’s useful,’ Sirius muttered. ‘Knows all the crooks – well, he would, seeing as he’s one himself. It pays to have someone like Dung around, he hears things we don’t. -Order of the Phoenix

Mundungus, como um criminoso de carreira, como as habilidades necessárias para se esconder e tem inteligência de rua.

‘Mundungus, of course,’ said Sirius, and when they all looked puzzled he laughed. ‘He was the witch under the veil.’

‘That was Mundungus?’ Harry said, stunned. -Order of the Phoenix

Mundungo oferecendo uma idéia sobre a melhor maneira de esconder Harry durante uma extração, é exatamente o tipo de conselho que a ordem realmente tomaria dele. Desde toda a sua vida é sobre se esconder, evitando aviso e desorientação.

‘What do you think he was doing?’ said Sirius impatiently. ‘Keeping an eye on you, of course.’-Order of the Phoenix

Depende de nosso conhecimento mundial que o plano pode ou não ser uma boa ideia, o fato de que no mundo Dumbledore originalmente surgiu com ele, e afirma

said Dumbledore. However, you must plant the idea of decoys; that, I think, ought to ensure Harry’s safety.

Significa que, no mundo, ela tem uma lógica sólida, e assim, com o plano de fundo de Mundungus, estabelecendo um plano logicamente sólido, não será preciso muito para convencer o resto do pedido.

Está implícito que a Ordem não tinha outras idéias que eles achassem que poderiam funcionar. Assim, Mundungus convenceu-os simplesmente propondo uma ideia que eles achavam que poderia funcionar. Da conversa quando o plano é explicado a Harry (minha ênfase):

"Let’s have no more arguments. Time’s wearing on. I want a few of your hairs, boy, now."

"But this is mad, there’s no need —"

"No need!" snarled Moody. "With You-Know-Who out there and half the Ministry on his side? Potter, if we’re lucky he’ll have swallowed the fake bait and he’ll be planning to ambush you on the thirtieth, but he’d be mad not to have a Death Eater or two keeping an eye out, it’s what I’d do. They might not be able to get at you or this house while your mother’s charm holds, but it’s about to break and they know the rough position of the place. Our only chance is to use decoys. Even You-Know-Who can’t split himself into seven."

Eu acho que você já respondeu sua própria pergunta na pergunta em si; no entanto, vou deixar uma resposta.

‘You will have to give Voldemort the correct date of Harry’s departure from his aunt and uncle’s,’ said Dumbledore. ‘Not to do so will raise suspicion, when Voldemort believes you so well-informed. However, you must plant the idea of decoys – that, I think, ought to ensure Harry’s safety. Try Confunding Mundungus Fletcher. And Severus, if you are forced to take part in the chase, be sure to act your part convincingly ... I am counting upon you to remain in Lord Voldemort’s good books as long as possible, or Hogwarts will be left to the mercy of the Carrows ...’

Now Snape was head to head with Mundungus in an unfamiliar tavern, Mundungus’s face looking curiously blank, Snape frowning in concentration.

‘You will suggest to the Order of the Phoenix,’ Snape murmured, ‘that they use decoys. Polyjuice Potion. Identical Potters. It is the only thing that might work. You will forget that I have suggested this. You will present it as your own idea. You understand?’

‘I understand,’ murmured Mundungus, his eyes unfocused ...

_{Deathly Hallows}

Snape usou um feitiço Confundus para plantar a ideia em Mundungus de sugerir à Ordem que eles usassem a poção Polyjuice / o esquema de sete Potters para tirar Harry da No. 4 Privet Drive. Mundungus apresentou essa idéia em uma reunião da Ordem, e foi escolhida pela Ordem como o melhor método para usar o Harry. _{- Relíquias mortais}