What about (3): A presidential candidate pops up in the other party who you’d vote for if they won the nomination? I’m sure that there are some people out there who don’t identify with either party, and would vote for Kasich over Clinton, but Sanders over Trump. Why should they be shoehorned into a Trump vs. Clinton match-up when there are candidates on both sides of the aisle that they would prefer over the front-runners? Why shouldn’t they be able to put their best candidate into both sides of the race?
Wait. You have to register as an independent? That makes no sense to me.