Simplest machines
The simplest machines have very few "key poses", and can be accurately described as A > B > A, a true 2-step machine.
Some of the simplest machines defy this description and are arguably simpler than the standard 2-step machines: 1 Base foot slides. To the best of my knowledge, I created the first of this kind, the Hip Slide:
There are also machines that pass through intermediate poses that are arguably not "key poses" and can be described as going from A > A.
The Rirata can be described as Reverse Inside Star to the same Reverse Inside Star:
Similarly for the Risotto, with Reverse Inside Star on Hands:
The Spice (with intricate footwork) can be described as Inside Star to the same Inside Star:
The Spice can be compared to the more standard 2-step machines I or the I Infinity:
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