One of the few Apple bears on Wall Street was clearly caught off guard by the company’s mind-blowing fiscal Q2 results. Here is why Goldman Sachs lifted its sell rating on Apple stock.

With this being said, Wall Street's bull market is on the cusp of unwanted history. Arguably, the best valuation tool that allows for the clearest apples-to-apples comparisons is the S&P 500's Shiller ...