I think the Green-EFA group is so heterogeneous because it's a union of a bunch of people that don't really have anything to do with each other. The Greens don't have anything to do with a bunch of regionalists and separatists, and the various EFA people don't necessarily share anything either (is there really that much in common between Basque and Scottish and Flemish nationalism?). If it were just the greens the group would be much more uniform, or at least as uniform as any european parliament group is
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