0 SpA Togekiss Water Pulse vs. 0 HP / 4 SpD Tyranitar in Sand: 68-82 (19.9 - 24%) -- possible 5HKO
0 SpA Togekiss Dazzling Gleam vs. 0 HP / 4 SpD Tyranitar in Sand: 134-162 (39.2 - 47.5%) -- guaranteed 3HKO
Sorry if I'm misunderstanding this, but isn't Dazzling Gleam strictly better than Water...