WASHINGTON (Reuters) - Treasury Secretary Timothy Geithner said on Sunday that proposals to more tightly regulate the financial sector are not a threat and will ultimately be a benefit to banks by making them more credible. Interviewed on CNN's "GPS" program, Geithner said the financial crisis had exposed the degree to which banks had strayed from their traditional mission of channeling Americans' savings into growing businesses. When trouble developed because of excessive risk-taking, customers suddenly went from "banks falling all over themselves to lend them money at unrealistic rates, to credit drying up in a heartbeat," he noted. "That system...