I've never shorted a stock before, but my understanding is that I *borrow* shares, then sell them and cash the proceeds for $X. I can then later buy the same shares (covering at a lower price) at $Y and return them to the lender. My gains would be $X - $Y.
Why would I have to sell the shares that I own currently in a long position?
Isn't that what tutes do all the time by hedging both a long and a short position?
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