several ways

1 some brokers can locate the shares at a cost b/w 4-6%, which offsets most of the edge;
2 you can construct synthetic short with options.
3 when vol is low, or when mkt is going one way (grinding up in particular), there is no edge for shorting those to collect theta. instead you lose due to compounding.

just my 2c.

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• 老兄是专家这些你都做得到。我早就洗手了 -关键字- ♂ (325 bytes) () 11/30/2014 postreply 16:41:48