I am the PA, I'm Andrew, Colombian. My wife is Canadian, her name is Juliana. The immigration officer asked me about 6 questions, yes, but the guy that asked me questions first asked me like 30 or more, I was in the interview booth with him for almost an hour or so. Two different people interviewed me at different times, one wasn't an IO and the other one was. First person to interview me did it in Spanish, and then he was with the IO for the second part of the interview, as an interpreter. The IO was Canadian, the other guy was Colombian. She was using interpreter but noticed I understood all she was saying (I was answering in English, without waiting for the interpreter to say things in Spanish) so she asked me if I wanted to do it in English and I said yeah. I think in my case it was important because one of their concerns was that my level of English was really high yet I have never left Colombia. I am sure they have a "quota" but I'd say it's for quality standards. They have to have interviews, specially in countries where people gain a lot by getting PR to Canada. I wouldn't know about the rehearsed thing, however I did notice that when I was answering questions, I didn't need any time to think about my answers, they'd just come out naturally because they were all true. Also, I think they really liked it that I was giving specific details, my answers were not just a "yes, we did that" but more like, "we did that because of this and that, and that day this happened". For example, they asked me how we kept the marriage going, and I said we tried to do all the things normal couples do, then gave her specific examples of how we do this. I mentioned how two days before the interview (this Monday) we watched a movie on the internet, and I told her the specific movie, and even that Tom Cruise was on it. I think that really makes a difference, if you provide specific details along with your answers, it will be easier to believe them.