Looking into data on that, it looks like you're right that crime rates tend historically to be low in Norway; they've stayed for the most part stable in the last 60 years as has the overall prison population. I suppose that suggests that it's more the nature of governing than prison structure itself that impacts crime rates. I would think, though, that nature of prisons would have a noticeable impact on recidivism rates, but I can't seem to find any historical data on that, only data since after the establishment of Bastoy (the older of the two I previously mentioned).
However, one of the articles I previously referenced is a white paper from the US DoJ, a metastudy that collected data from a wide range of past research efforts into the most effective means of recidivism reduction in practice, and there's essentially full agreement within criminology, psychology, and sociology that rehabilitative methods are key for minimizing inmate recidivism. You might want to give that paper and some of the others it references a read-over if this is something you're interested in.
However, one of the articles I previously referenced is a white paper from the US DoJ, a metastudy that collected data from a wide range of past research efforts into the most effective means of recidivism reduction in practice, and there's essentially full agreement within criminology, psychology, and sociology that rehabilitative methods are key for minimizing inmate recidivism. You might want to give that paper and some of the others it references a read-over if this is something you're interested in.