Depends who you are interviewed by. If that's a PM and Tech Lead of the project, then the correlation stands - the harder an interview will be, more challenges you will have in your daily job. I would say that good PM and Tech Lead are looking for the people for their project so they should be highly interested in hiring someone who is capable of doing such stuff. So in this case I would rather say that probably the stuff you were asked at the interview, that's what you will do on this project.
Huh, have you ever seen these guys? The ones that are doing some secret magic stuff day by day - interviewing people and architecting things.
I would rather consider this as a bad practice in outsourcing because these people are very likely to don't know the context of project you are applying for and that means there could be a lot of irrelevant questions. That means there could be a huge gap between what you've been asked in the interview and what you will be supposed to do. That being said, I would rather call such interview not the best one because it doesn't show whether you are qualified enough for this job.