If you take a look at it, Irving proposed a 285-degree crankshaft, not a 270-degree one. Essentially, the piston moves the fastest when it's at 75 degrees, not 90 degrees, so a piston's true half ...

She performs an incredibly impressive handstand on dumbbells and then takes it to the next level by ending in a position where her legs are at a 270-degree angle from her head.