One thought about the interview is that Bp. Fellay was sandbagged in order to make him look bad for something later on.
After regularization occurs, this interview can be used to tell Fellay to step down as Superior General and Rome can command a more "pastoral" and less divisive leader be put in place.
That could be it.
Others have said it's a "test" or "rite of passage" --
I could just see a Roman official telling +Fellay: "I tell you what. Look up 'Conflict Zone' and schedule an interview with them. Tell them ______ sent you. We'll talk more after your interview airs..."
By getting this kind of confrontational barrage, they can test how "optimistic" and "politically savvy" +Fellay is, they can see if he is willing to excuse Vatican II, and so forth. They need to know where he's at.
After this interview, I think it's plain for all to see.
I realize that Conflict Zone was very adversarial and aggressive, but that is precisely what made it a very good test. These questions would ALL have been asked by various persons/groups over the next 5 years after a "deal" was made anyhow. Why not get a preview of how +Fellay will respond to these questions -- BEFORE canonical recognition is given?
Rome doesn't want any surprises. They want to see +Fellay weaseling and "sinning by omission" before they pay for the goods.
For example, when they confused "modern" with "modernism", he emphasized how the SSPX uses "modern things" like cell phones, Internet, etc. and conveniently didn't teach us about Modernism (which controls the thinking of the whole Conciliar Church) at all.
Or when the subject of men and women being equal came up -- of course the answer is "I must distinguish" but he focused on the modern world's point of view, how we're all equal before God (true). Rather than getting into St. Thomas and how men are superior in certain ways (also true). That wouldn't have won him any friends.
Come on, Bishop Fellay! Give us the quote where St. Thomas Aquinas says that
were it not for reproduction, God would have done better by creating a second man for Adam.
So when there were two aspects to a problem -- a popular one, and a not-so-popular one, he always addressed the aspect he knew people wouldn't have a problem with.