While I often agree with Goldman and think that he backs up his ideas well, on this point I disagree. I don't disagree that Nomar was a problem in the clubhouse. He may well have been, but a problem in the clubhouse who hits .333 with 30 homers will stay a problem in the clubhouse, i.e. not be traded. Nomar was traded because his defense was not up to snuff anymore due mostly to his injury. The fact that he was a negative in the clubhouse might have played a small role, as did the fact that the Sox would lose him to free agency at the end of the year.
As far as the whole moneyball thing, people often misread moneyball as a treatise on on-base percentage and patience at the plate. Moneyball is bigger than that. Its about value, and more specifically reading the market to determine what is undervalued at any one time, in order that someone (or some team) with limited resources can in effect buy low and have success.
How does this relate to the Nomar trade? Theo realized that he had to upgrade the Red Sox defense, and in this case, he was able to get two undervalued players that played key roles for the Sox down the stretch last season, for one over-valued player who would not have. Thats as 'moneyball' as it gets.