2. Who really benefits from a third party
Third parties arise as split-offs when the two main parties fail to listen to their base by nominating a candidate unacceptable to the majority of their voters.
As such, it is a thundering message of party failure. To keep it from happening, the parties must work out the differences between their underlying constituencies and nominate someone who best represents what the party stands for.
If it were not a real possibility, each party would end up not caring about their base, since voters [like you] would vote for them no matter who they elected. Because of this, the answer to your second question is that all conservatives benefit by holding the Republican Party's feet to the fire with a credible threat of a third party.
ONLY by a severe third party challenge, or at least the viable threat of such, does the Republican Party get the message... They never see the light. They only feel the heat. No heat, no change.
No More RINOs - Including RINOmney!
Third Party Candidate - Strom Thurmond - New Party - Nope
Third Party Candidate - George Wallace - New Party - Nope
Third Party Candidate - Ross Perot - New Party - Nope
I'm afraid history is not on your side - unless you are a dimocrap. I believe in each of these elections the dims won, so if you're working for 0bama, then go ahead promoting a third party.