Heavily-shorted Fusion-io (FIO +11%) closes up strong after investors decide EMC's (EMC -0.5%) VFCache product is more bark than bite. Fusion-io CEO David Flynn declares VFCache, which EMC used a Q&A call to promote, to be far more costly than Fusion-io's solutions, and deems it an attempt to hide the inadequacy of EMC's traditional SAN storage hardware for high-end performance needs.