First, the Gravity Hold is very useful in a few specific circumstances, but it doesn't get a lot of uses from its energy bar, so you really have to pick your spots to use the screen clear...especially since it takes two or three shots to make some enemies go away.
As for the stage, outside of the collapsing bridge where the letter is and the auto-scrolling elevator of death, it's not very notable. Gyro Man is kind of a joke with the Gravity Hold, but if you don't have that, he can be a massive pain due to having cloud cover most of the time.
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