Whatever use true-crime author John Follain is, he's useful in comparing and contrasting the way he puts things, compared with the way the characters who confided in him put things. This is a window to understanding if Giuliano Mignini had had the idea for a "frame-up" right from Nov 2nd.
I think an answer can be found in the way Follain differs from Mignini in relating the events leading to the 5:45 am, Nov 6 "confession" Knox signed. Given that Follain could only have got his details from Mignini - why the differences, esp. when compared with what Mignini told Drew Griffin of CNN about that night? John Follain writes an account of the time Mignini spent with Amanda (p.136-7, A Death in Italy) which is at odds with what Mignini himself told Drew Griffin of CNN in 2010.
The biggest difference is that Mignini tells Griffin that he's careful not to lead Knox at all, mostly likely because Mignini knows he needs to preserve the sanctity of "spontaneous statements" as much as possible. Not only does this mean (by his own admission) that he can ask her no questions, but he cannot "lead" her as well. For spontaneous statements to be spontaneous, they need to me, ah, er, spontaneous.
Right from the start of Follain's account, you'll see what's wrong. the critical time "5:45 am" is the time the 2nd memorial was signed, not the time it began. Also, in the CNN interview, Mignini goes to great pains to say why Knox did not need a lawyer - Follain has Mignini directly saying to her that she needed one, but refused. Is this Follain inventing facts to help Mignini along; or is Mignini the two-faced liar, telling Follain one thing and Griffin another?
Also, the bit about "Amanda had been unburdened" by accusing Patrick was said by Mignini to be his own insight BEFORE Amanda's statement, not after like Follain relates.
Who's the liar here? Mignini or Follain?
Follain said:
At 5:45 am, Mignini summoned Amanda. Speaking through an interpreter, the prosecutor asked if she was willing to make a statement. He opened a copy of the penal code and read out an article to her, which the interpreter translated. The law, Mignini explained, said that he couldn't aske her any questions and would limit himself to taking down her statement. 'You talk, and I listen,' Mignini said. He pointed out that from now on, anything she said could be used against her, and she was entitled to a lawyer. Amanda said she didn't need one. As he talked, Mignini noticed a red mark in the middle of her throat, but thought nothing of it.
Amanda wanted to speak, she explained, because she was deeply upset by Mereith's death, and very afraid of Patrick, whom she had met at about 9 pm. 'Patrick and Meredith went into her room, and I think I stayed in the kitchen. I can't remember how long they stayed there....
Watching Amanda Mignini had the impression that Patrick terrified her. He didn't doubt her sincerity; he thought she had unburdened herself in accusing him and had then cried with relief. The prosecutor hoped Amanda might tell them the rest of the story. 'Come on, go on talking. Tell us what happened, you can get this weight off your shoulders, he said to her.
Follain concludes this by saying, "What Amanda revealed fitted Mignini's theory that someone inside the flat had let an outsider in who first sexually assaulted Meredith and then killed her....." Follain then has Mignini say aloud,
"Amanda may be a fresh faced beauty, but she's also an actress, very calculating and a shameless liar."
Right there in his text, Follain contradicts himself.... or at least contradicts Mignini's account. If Knox is such a shameless liar, why go out and arrest Lumumba solely on Amanda's say-so, as Follain later relates is the reason Mignini had Lumumba arrested?
The point is, I don't think there's evidence, really, that Mignini was going to pin this on Raffaele and Amanda right there from the early afternoon of Nov 2.
The trouble is: John Follain implies heavily that the PLE were right to suspect Raffaele and Amanda, right from the "pooh" incident, where Napoleoni is annoyed with Raffaele on Nov 2 for being so insistant that the pooh be noticed.
With respect to Grinder, the issue is not the true-crime genre itself. It is that John Follain writes such an inconsistent narrative, wanting to have it both ways. Follain wants the PLE/Mignini to be right in suspecting them from the start, but also be caught by surprise at the Nov 5/6, all night interrogations.