It seems like pissing off Massei is only a minor factor with regards to the political issues involved with this case and we just aren't sure about what the normal way of dealing with those in Italy is.
A whole lot of people think that Knox is guilty and that the prosecution is not horribly flawed. Flying in the face of that kind of thing is difficult. Although courts certainly do stand up to prosecutors occasionally, they pick their spots and confronting prosecutors that still remain popular is difficult. In the end everything is political and spending one's political capital is done carefully by every political/legal leader. Whether Hellman chooses to spend some political capital here or not is still an open question.
Even without that, the fact is that a lot of people think RS/AK are guilty. Some of those people could be on this jury. I just read the responses to a link somebody posted above about Lumumba. A lot of those people were hanging their hat on the "confession" and some of them understood that it wasn't a confession exactly but still thought the fact that Knox said she was in the apartment at the time of the murder was very strong evidence against Knox.
As one who thought there was a 99% chance that OJ Simpson would be found guilty in his first trial based on the simplistic notion that overwhelming proof of guilt would get him convicted I am very wary of what can happen here. My mother in law still thinks Simpson was innocent. You only need a few people that think like my mother in law on the jury and AK/RS might be found guilty. Their view of the world is ruled by their gut feel and if Knox's behavior's or situation pisses them off in some way Knox will be found guilty. Facts, no matter how damning of the prosecution's case will be ignored or selectively not understood.
Here is the difference, however: in the Italian system,
the judges (both of them; there are two)
are part of the jury.
That doesn't mean they will make better decisions, or be immune to the problems you mention (cf. Massei!). But what it does mean is that
procedural rulings provide information about which way the court is leaning. This is not the case in the U.S., where the judge is separate from the jury, and what goes on in the jury room is a total mystery until the verdict is announced.
Instead, it's more like appellate cases in the U.S., which you can often predict by the questions the judges ask, and even whether they agree to hear the case or not. In 2000, it was clear in advance how
Bush v. Gore was going to come out, because not only did the Supreme Court agree to take the case, they actually ordered a stop to the ongoing recounts, which was a rather extraordinary step.
Here, the analogous extraordinary step is the appointment of Conti and Vecchiotti. So the "who knows what these people are thinking?" element of surprise isn't present in this case. We can read the tea leaves by looking at how the appeal has proceeded.
If Hellmann's court thought there was enough evidence to convict without the DNA, they wouldn't have ordered the review. It would have proceeded directly to arguments, the appeal would have been over in January, and the case would probably be in
Cassazione by now.
That's the plain truth. If Hellmann and Zanetti saw the case the way the guilters see it, the appeal wouldn't have taken any longer than Guede's.