Originally Posted by Fat ZandgaiaX
Double Dance doesn't mean trying to get both boosts, it is meant to use that set-up move that you think is useful for that situation.
However double dance seems neat on paper, but I don't think it can work. There's enough priority that even Raichu has trouble setting up, and do note that Raichu fares far better in NU than Pikachu will ever be.
Alas, Pikachu just won't do. Light Ball is an interesting item to have, but since only Pikachu can use it, it's fairly useless in the end: Pikachu is frail, has a 'meh' speed and lacks good breaking-power.
But the situation DragonBorn described makes use of both set ups, Double Dance can work, but it's the situation in which both boosts are necessary that it will cause problems. Alas, this will never be a situation, unless you play against a player who's either bad or not suspecting it.
I agree with the rest of your post, as I tried to say myself;
Raichu will always be way better than Pikachu in NU, although it's a good mon for a cute team. :3