Yeah, the agent behind the booth makes the decision most of the time. in a minute or two after a couple of questions, without needing to consult any superior staff. Much quicker and more straightforward that I had imagined. There are only a few occasions where they have to escalate it and the applicant would hear the decision in a week or so.
When I hear "visa interview", I think of turning up in a suit, going to a fancy office and spending an hour discussing your whole life with an interviewer (or several). But it's actually just turning up to a booth that could be in a post office, talking for a minute or two and getting an immediate decision most of the time.