I suspect that computers will help out quite a bit. Similar to other topics, computers will first outperform most people, then ultimately everyone, but computers plus people will outperform just computers.
It's a policy I largely agree with.
It costs around £40k/year to keep someone in jail, not including the opportunity cost of lost productivity.
Will the prospect of an eight year prison sentence make someone less likely to commit the original offence(s) than a four year sentence? Probably not.
Will it reduce the risk of reoffending once they are released? It will probably have the opposite effect.
"You are an habitual criminal, who accepts arrest as an occupational hazard, and presumably accepts imprisonment in the same casual manner."
Now, apparently the guy never thought he'd go down for all of his crimes, but he knew arrest was a real risk. Same with prison. I'm afraid I don't have a strong opinion on what the best choices are that a criminal justice system can make. Clearly you aren't going to scare people straight with hardnosed punishments though, because their evaluation of risks are not what you think they should be.
Super cool site. That data would be pretty fun to play with though, age/offense count/previous offences/family etc would all be cool buckets to play with. Plus all the things I don't think of off the top of my head