[magister_negi_magi]

That FS of Marth's seems pretty hard to miss with if you don't just throw it out randomly. You can cancel into a FS from a regular combo, so anyone with a drop of skill should be able to make it connect. Any few frames of lag at all is enough to get it in. Like Squeek said, other FSs are much more easily avoidable. You can just WALK in the direction that Lucario's Master Spark is sweeping and it will miss, small stage or not.