That is exactly what they do. They buy in and then lend to shorts who are individual investors. They are sucking them in letting the price drop so more and more short. when it gets low enough they buy more and slowly call in the shares they lent out. THis forces the shorts to cover which leads to the stock price rising. This can only be done when you are as big as GS or others. Individuals short or long get killed when they get caught in these traps. Just give it time, they are building their position for sure.