Nope...I can make it switch on demand. I can keep it spinning in either direction indefinitely, or switch it back and forth in a manner of seconds.

These things are always a little difficult to explain, but try this. As much as possible, concentrate on only the lowered foot - try to ignore the rest of the image, as difficult as that might be for you boobie addicts.

Since this point of the picture has a much smaller diameter of content spinning away from the center axis, it's easier to "trick" your mind into seeing the foot spinning in either direction.

Once you see the foot change directions, look upwards and the rest of the image will follow. With a little practice, you can probably get it to switch almost immediately.