It's insanely good at reintegrating branches multiple times, something that it's predecessors like SVN were notoriously horrible at, which has allowed us to have long lived branches that aren't suicidal to finally merge. You can't evaluate a coworkers branch without switching contexts or creating a merge artifact (and thus entangling your branches). Any changes you make can be dragged visually from one branch to another, committed and continuously worked on without switching branches or creating unneeded dependencies between branches or changes.