Before revision:  In particular, they explain why so manyheuristics perform well in practice at finding high-scoring partitions, why these heuristics can disagree on the composition of the identified modules , and how the estimated value of Q_max should be interpreted. Further, they imply that the output of any modularity maximization procedure should be interpreted cautiously in scientific contexts.
After revision:  In particular, they explain why so manyheuristics perform well in practice at finding high-scoring partitions, why these heuristics can disagree on the composition of the largest modules and the distribution of module sizes. These results imply that the output of any modularity maximization procedure should be interpreted cautiously in scientific contexts.