The projections do include individual player statistics from those 120 games. They just don't throw out the first 40 games. What human factors are you considering that wouldn't be picked up by stats? Personally, I think they played over their heads the last 120 games. They had a mediocre bullpen that hardly blew any games. I think there was some luck involved there. The first 40 games were flukey too because every hitter was slumping at the same time. A lot of people give credit to Hinch for the improvement, but wasn't he also the manager at the beginning of the season?
I think they'll do better than 74 wins, by the way. I just don't think the improved record at the end of the season should be used to pump up a projection.