Conor Friedersdorf will not vote for Obama or Romney. He instead argues that voting for a third-party candidate is what a moral, conscientious, and informed American should do. I do not agree.
For the sake of argument, let's assume that the implausible happens November 6th and someone like Gary Johnson or Jill Stein gets elected. They must immediately form a transition team and start selecting viable Cabinet nominees. Who would they pick? Would there be any potential picks who have experience at a national level, the competency to run entire departments, and the credibility both home and abroad? Before they even get there, are there even staffers prepared to man a transition team?
Again, let's assume there are credible, competent people who align with this independent candidate, they are selected and now must go before Congress to be approved. Obama, with a near super-majority, had immense difficulty getting his nominations approved and for much of his first term was lacking a fully-staffed Cabinet. Now, facing two opposition parties, how will the approval process proceed? Any of Stein's appointees are nearly guaranteed to be far too liberal for Republicans and even a third of Congressional Democrats. Johnson would have to either sacrifice his social (to appease Republicans) or economic (to appease Democrats) stances to get anyone appointed. Or they would have to select from the majority party's Cabinet candidates and have an entire Cabinet that does not line up behind the President.
Once more, let's assume the third-party President (TPP) somehow gets a full Cabinet that is aligned with their beliefs and campaign promises. The Inauguration is now over and it's time to get to work. TPP sends his first proposed bill to Congress and... Congress (no Independents in the House; one Independent in the Senate [two if King wins in Maine, which he is projected to]) flatly rejects it and writes their own legislation. The normal gridlock occurs between Democrats and Republicans and FINALLY one bill out of 100 make it to the Independent President who... vetoes it. Lacking the two-thirds vote to overturn, no bills are passed for four years... Or the TPP signs the bill he does not agree with, and his Independent status means nothing, legislatively.
Obviously, it depends on who the TPP is and what stances they hold, but with the current gridlock between two parties, the gridlock would only be worse with a third party introduced.
A viable third party must start with local/state elections. To borrow a concept from video games, a third party has to "level up" enough and recruit a big enough party to take on the final boss of the Presidency. As third-party Senators and Representatives are elected, their staffers and advisers get more experience, and potential Cabinet appointees are created and incubated. A coalition of like-minded Congresspeople are in place to create and pass the TPP's bills. This also eases the two current parties into slowly relinquishing power and opening them up to compromises to get anything done.
This post is more conjecture than I typically like to do, but I really can't be optimistic about a third-party candidate when the two-party system is already so dysfunctional. Even if they were to start winning seats in Congress this year, a third-party is very far away from creating a competent Presidential administration.