Grant George, a longtime head of software testing at Microsoft, is leaving the company, AllThingsD has learned. Like Jon DeVaan, who announced Monday he was retiring from Microsoft, George was left without a clear role following a September reorganization of the Windows unit. That reorg followed the departure of Windows head Steven Sinofsky. Sinofsky, who worked with George on both Office and Windows, praised the contributions George made at Microsoft. “Grant always represented the pinnacle of customer focus,” Sinofsky said.