Okay, please take mckeeman's and my word for this, I don't know what the rest of you are saying.
First, JF's trick is a flat 9, not a rockbottom.
And second, a rockbottom is basically an inverted bio, CR does one in a ski movie (I forget which)... the shot shows two tables. On the first table he does a d-spin, and the second is a rockbottom 7.
Like I said, basically an inverted bio. Think 180-backflip-180. That's rockbottom.
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