Take a Codex squad of Marines, give it a missile launcher and plasmagun, then combat squad it with the missile launcher in one and the plasmagun in another. Now you have two actions from one choice, at the cost of another kill point.
Now, having a bunch of actions won't win you any games, but I'd say that pretty much, all other things being equal, the side with the most actions will win just about any game. Of course, the tricky question is what makes two sides equal and that one, I'm going to cheat on and leave vague.