Put yourself in the shoes of a detective. You have to be able to think like a criminal. You have to have the mind of a chess player, two steps ahead. Funnily enough, as it takes one to know one, there is invariably a game that develops of the criminal trying to outwit the cop and the cop anticipating the antics of the perp.
Raff has the chess player mind. He precluded the cops on several occasions, for example, explaining away Mez' DNA on the knife blade as when he pricked her hand and the shoe prints as, "someone must have borrowed my shoes".
So we see a huge psychological battle develop between Amanda and Raff and the police. The police have an advantage. They have seen it all before (for example, staged burglaries), they have heard all the stories (for example, "I can't remember", seen all the tactics (for example ringing up the dead person, as an alibi).
So, you are an ambitious cop and you are faced with an icy cold supsect determined to outwit you. How would YOU handle it? Do you ensure you've received all the latest interview techniques and received loads of experience? Of course you do. You send in your best cops to deal with it. You don't send in someone who's going to have the whole thing tossed aside as a mistrial.
The guy in the article misrepresented Reid in his three day course and in any case, police in the UK have adopted PEACE, and probably in Italy.
How do you know Italy uses Reid? It's a guess, right?