How can the price go down on a limited resource ? Eventually a shorter must buy BTC to pay back the BTC that he/she borrowed (that's how shorting works). But BTC is getting more rare every day. In every dip on the markets, there is some farmer in zambia who bought his first bitcoin. Since there are a lot of farmers left in zambia without bitcoin, the transfer is still going from the few to the many, and no future contract can ever prevent that.
BTC futures are cash-settled, so you never need to buy or sell Bitcoin if you are speculating, for example, in order to drive the spot down, and load up on actual BTC at a lower price.
aminorix , i am always reading your posts and find them very interesting. What do u expect will happen tomorrow with the release of bitcoin futures , in mean impact on XMR. Could we go higher this year or is all that for first quarter next year when new stuff is released