You don't hear a lot of odes to partisan polarization in Washington, but it's a social and political phenomenon that can create substantial benefits in terms of bringing coherence to the policy agenda. A case in point: ethanol subsidies. The old CW was that failure to support lavish subsidies for turning corn into vehicle fuel on faux-green grounds would be a serious impediment to one's presidential aspirations. But a very good Alex Guillen article in Politico notes that this year only Newt Gingrich is talking ethanol. The other contenders aren't exactly bragging about their opposition to subsidies while cruising around the state, but they're not pandering to narrow Iowa farm interests with opportunistic exceptions to free market ideology.
Guillen explains some of the in-state dynamics that have led to this outcome, but I would put polarization on the list. As party activists become more committed to ideological rigor and better-informed about the content of conservative ideology through partisan media sources, they become less interested in using their influence to wield the Republican Party as a vehicle for Iowa interest and more interested in using their influence to wield the Republican Party as a vehicle for conservative ideology. From an economic policy point of view, this trend and its opposite number on the Democratic side is a good thing. One of the most pointlessly wasteful things that our government does is hand out large quantities of largely offsetting place-to-place transfers. To an extent, that's just bound to happen in a geographically large and demographically diverse representative democracy. But to the extent that citizens becomes ideologues and parties become tools for ideological mobilization, the tendency to mobilize public policy in unprincipled ways gets muted. Conversely, the classic alternative to partisan polarization in a legislature is very much the opposite of highbrow national interest compromise, it's a state or regional block of legislators joining hands across partisan and ideological gaps to preserve some random interest group giveaway.