Quote from stevegee58:
Here's my understanding of what's going on (please correct me as needed MacroEvent). I've seen similar approaches in FOREX:
You can't be both long and short on the same instrument in the same account, hence 2 accounts, one for long, one for short. Note that he has more contracts at his reversal points. This has the effect of nullifying the other account's position and also adding in the direction that the market's going.
You cash out the winning positions when the market reverses again and let the losing positions gain in value. You're always "in" the market this way.