Stocks switched back into climbing mode this morning, after a better-than-expected durable goods report. The Dow rose 76 points, bolstered by GE's 4% surge, while the Nasdaq and S&P each gained about 1%. Durable goods orders rose 3.4% in February, defying analyst expectations of a 2% decline. But one economist urged caution. “It is much less impressive than it looks at first sight,” he said. “It cannot possibly last.” (More stock market stories.)