When I do a corkscrew, my hands are quite close together and the poi move quite fast. There is only one other guy I know who naturally does it fater. It looks fairly different to the animation in poi lessons considering it's the same move.
Two variations I have come up with involve wraps to reverse the direction of the corkscrew.
The first and easiest is to get both poi heads to hit the back of your thigh or arse at the same time. The second and slightly trickier is get each poi head to wrap each of your legs.
The trick to making it work is to slow down the poi a little as they come from above to below. the must hit around the same time, then you must reverse the order in which they go back up! The first to come around and wrap must go back up second.
I naturally corkscrew (no comments!) anticlockwise leading with my right poi. When I wrap, the right poi comes down from above and wraps my right leg. the left poi comes down and wraps my left leg then leads the right poi going up over my head, travelling clockwise now.
You can combine wraps for both directions of travel, reversing as many times as you want.
Hope this doesn't confuse you all too much

If I can fire up my bosses digital camera, I'll attempt to film this.

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Your parents were wrong
Fire is good
Play with fire