His point is the number of people making predictions is high enough that it raises the bar for people to stand out from the pack. Basically run an ANOVA test on 10 groups vs 10,000 groups and it takes a larger divination to stand out from the pack.
PS: It does not matter if there is a system behind their predictions, what matters is how well their predictions hold up over time. Otherwise your just: http://xkcd.com/904/
PS: It does not matter if there is a system behind their predictions, what matters is how well their predictions hold up over time. Otherwise your just: http://xkcd.com/904/