Even Stock Optimists Grow Nervous About Rally

(Bloomberg) -- The most vocal optimists are getting skeptical of the never-ending stock rally.What once seemed sensible is starting to baffle even them. The S&P 500 is up 39% in 50 days and in the midst of its longest winning streak since February. A flattening virus curve, Federal Reserve stimulus and reopening plans explain a lot of it, they say. But with $7 trillion in value created and the Nasdaq 100 near a record, many big bulls are sounding distinctly...bearish.The S&P 500 rose 1%