That's the most recent advice from Morgan Stanley's Chief US Equity Strategist Mike Wilson. Wilson is keeping his price target for the S&P 500 at 3,900 — about 1% below the index's closing price on Monday — even though he expects the pace of the economy's recovery to remain strong. Ellen Zentner, his firm's chief US economist, recently raised her forecast for 2021 US GDP to 7.6% from 6.6% because of the large fiscal stimulus that's expected in the form of checks to Americans. So what gives, and why isn't Wilson following suit with a price-target hike? The S&P 500 index has already priced ...