Although I have not experienced any interview with such name, let me share my two cents.
Final rounds are typically applied by partners, with probably lots of years of experience under their belts.
Given that, they are the kind of consultants that are able to naturally discuss a business problem, being structured, insightful and straight to the point at the same time, while having a cup of coffee with a client. It is their ROUTINE. They are not going to ask for 30 seconds and a piece of paper. They won't have "time to think", during a quick chat during lunch or in the elevator.
So whatever they name this final round interviews, keep this in mind regarding final rounds:
* They usually require more of your business sense than your quantitative "fire power"
* There is reasonable chance that the case will be more like a conversation (versus the traditional on paper case)
* If that is the case, remember that although the interview might seem informal, you are still being tested at the same level (or higher) as if it weren't. So, ALWAYS be structured while brainstorming / discussing / wrapping up a case, even when someone says "just say what is on your mind"
* Act naturally and don't be "robotic". After all, this is indeed a conversation
I hope this helps =]