I'm sure someone has already said this but BP and Pecota have almost always been wrong. The one year they were right was in 2007 and that year they said the strength of the White Sox was their bullpen. Oops.
Having said that, I think that 77 wins is a fairly accurate representation of our win total this year. What I find surprising is that they think the Indians are better than the Royals, as the Indians have ZERO pitching. I also don't understand how they think the Cubs could have improved by 16 wins by Edwin Jackson and a closer in his 30s who has never thrown a pitch in a professional league in the United States. Their methodology makes no sense to me.