It's still not done because of the amount of leverage required. You need $2.50 left in your account for every share shorted no matter what price. That's designed to protect brokers.
So if you shorted 10,000,000 shares @trip2 covered at trip 1 you just made $1,000...big deal.
You had to have $25,000,000 in your account to do that so it doesn't make any sense. If you have that kind of money then you're probably not playing around with this stuff.
Some people don't know that rule that they made but it's been around for quite some time.
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