Reasonable minds will differ: One can certainly understand the paranoia surrounding the JFK murder what with all the strong competing forces working at the time. You have the Russsians, the Cubans, the Mob, the military, the CIA, and your wackjobs. Any one of these groups probably had it in for JFK to one degree or another. Now, the single bullet theory, while not making any sense, doesn't necessarily invalidate the prospect that Oswald did it. But, I look at it more from the perspective that for him to have done it alone, would have taken the alignment of every cosmic force available. He's not detected, he fires perfect, rapid-succession shots on a moving target from far away, he calmly walks away from the depository, again un-noticed. Then miraculously, he's found sitting in a theatre when no one saw him do it?
I dunno. It will never be solved to anyone's liking, but it doesn't mean we shouldn't try harder.