So, with five hits, at half damage each, you get slightly less damage than a critical hit. And you've burned five uses off of a Killing Edge, Brave Sword, or Vague Katti, just for less damage than a critical. I think I would take any skill in the game, even useless ones like Miracle, over Astra.
At least those don't actively hurt you to use them.
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xfd dude, it's just a popularity contest on the internets.
-Vlado