In March 2010, the court explained it had reduced Guede's sentence by 14 years because he was the only one of the three defendants to apologize to the Kercher family for his failure to come to her rescue.
In the initial version of this post ("Guede's sentence reduced massively for lying apologetically!", below), I didn't take into consideration that this sick joke was based on Mignini's fantasy that Guede was just a participant in the murder, and not the knife-wielder. So, this drastic sentence-reduction essentially amounts to Guede being rewarded for "confessing" that Mignini's fantasy was true, and for "apologizing" for "his" actions (or lack thereof) in the fantasy. This would mean that Mignini's fantasy was "proven" by a lie, instead of evidence and reason.
This also confirms my initial suspicion that GUEDE'S SENTENCE WAS ACTUALLY REDUCED FOR LYING IN SUPPORT OF MIGNINI'S LIES. The "judge" who reduced his sentence essentially admitted it!
Thus "proven," of course it thus "proved" that Knox was the killer. Because she would not "apologize" for "her" actions in the fantasy, her sentence was not reduced. This is the really twisted part of this sick joke, because it implies that Knox's sentence would have been reduced if she had "apologized" for "her" actions in the fantasy. But this would amount to "confessing" that she was the actual murderer, and no amount of apology would reduce her sentence significantly.
This sort of thing is why this court has been compared to the Mad Hatter's Tea Party. However, it's not the product of insanity, but evil. Mignini and his legalistic coven sat around and deliberately concocted this sick joke dripping with contempt for the human race, no doubt getting many a wicked laugh out of it.
This demonstrates that Knox's trial, from one perspective, was an "interrogation," the goal of which was to torment her until she "confessed" that Mignini's fantasy was true. THIS THEREFORE PROVES THAT MIGNINI IS CAPABLE OF HAVING LED THE INTERROGATION THAT PRODUCED KNOX'S SIGNED "CONFESSION."
Unfortunately for Mignini, the world was onto him because Knox's allies had gotten the truth-snowball rolling downhill. (He complained bitterly about being flushed out from under his rock into the light of day, an he quickly slithered back under it as soon as possible.) So Italy's "justice" system had to pretend to be an actual justice system until the spotlight was taken off of them. This explains the dichotomy between the results of the two "trials" - the first was normal Italian "justice" - a mass of lies - and the second was the result of exposing those lies to the world.
Revision: Clarified final paragraph