After a long run the markets are experiencing corrections. Some corrections are violent some are more orderly. The stampede to get out leads to such events. Short sellers have a marginal role in it. Bearish funds and bearish analyst always try to exaggerate their importance but as a percentage of total investors , they are minuscule.
The stampede effect probably is more due to liquidity drying up. Absence of buyers and bids lead eager seller wishing to reduce their exposure to bid further down, leading to cascading effect." Get me out at any cost" becomes the mantra. With most of the professional money managers and traders following risk management strategies, as market start going down more selling comes in to keep risk in control.Capital preservation becomes the mantra. So absence of willing buyers leads to more panic.
At some stage the stampede runs its course, the stocks reach compelling valuation zones and a set of buyers step in and the market stabilises.These set of buyers are usually the big speculators. Either it takes time or lot of selling in short time frame for the buyers to step in. If you study market turns over several years, most rallies after stampede selling start on a dime and offer some of the best buying opportunities. The question to ask is what happens after a crash. Markets rebound ferociously.