Western Digital (NASDAQ: WDC) stock was a winner by association on Wednesday, thanks to the latest performance of its long-standing rival. After market hours, its fellow computer storage specialist, Seagate Technology, delivered quarterly results that far exceeded expectations. With that, Western Digital's shares coasted to a nearly 11% gain that day. The Seagate stunner Seagate published its fiscal second-quarter figures just after market close on Tuesday, with both revenue and headline profitability gr ...