What are the costs associated with going short? They borrow the share from one of the longs, sell it, and wait until they are able to buy it back for less, which allows them to keep the difference. While they are holding it, do they have to make some sort of interest/dividend payment to the person they borrowed it from? Do they have to pay some up front fee to go short? I'm just trying to understand your comment about how the price per share of going short would decrease as the price per share of going long would increase.
Also, let's say you go short and the price rises. What recourse does the person you borrowed the share from have at that point? How do they know you will be able to cover the short?
Finally, how would you dynamically hedge the theoretical investment you described earlier that mirrors GLD?
I realize some of these questions probably apply to markets as a whole, but after reading your example it seemed like a good time to ask them.
You're not borrowing anything when you long or short derivatives.
The funny thing about this claim (which I wouldn't be surprised if true) is that the OP thinks they are SUPPRESSING gold prices, where in fact, all this leverage is probably inflating it. Think about the scenario where there is a run on physical gold because regulators are cracking down on leverage - the likely outcome is that, because paper holders KNOW it's impossible to get the physical gold, they will most likely dump their contracts in the open market causing gold prices to plummet.