Some argue that the actual issue is the creation of the national security state, which created (effectively mandated) a disconnect between overt governance and secret control. For example note that some of the "bullshit" you cite did not prove an impediment to progress made prior to '64. In fact, one could argue that this focus on the political theatre is somewhat irrational given the implicit acknowledgement that the parties are disconnected from quaint notions of "American democracy".
It is reasonable to challenge that with the reality of actual political conflict in the socio-political arena. As for this cynic, I see the partisan jostling as internal dynamics of an elite that compete for available social, economic, and (petty) political advantages and resources, (ab)using demographic characteristics to marshall support.
tldr: I think the game of baseball perfectly captures the architecture of the american system. (hint: site sections can also be informative..)