[...] here's a question for the people who keep shouting that tech workers and their money are ruining San Francisco: Some of them right here, like the Excelsior district, just a few blocks from the trendy Mission, which the critics say the tech workers are ruining. Texas Gov. Rick Perry came to Silicon Valley a year ago to roll out the red carpet and encourage tech companies to move there. Twitter has been the vanguard of a wave of tech companies that are revitalizing that blighted stretch of the city. They don't like it. [...] there are the employees who commute on the tech shuttles - the "Google buses" - to Silicon Valley and other points south of the city. According to the recent Chamber of Commerce survey, affordability is the city's No. 1 problem. Efforts are being made to find ways to keep families and blue-collar workers here. Right. Because she's the problem.