From the IRS' standpoint, it kind of makes sense: 501(c)4's whose primary purpose is political is in violation of the 501(c)4 rules.
They need a better way to target 501(c)4 abuse that doesn't make it seem like they are targeting an organization for additional scrutiny based strictly on political viewpoint. But, how exactly are they supposed to do that, as those organizations that are most likely to be in violation will necessarily be political in nature.