Investors have had a couple days to digest the strategic partnership Microsoft and Yahoo jointly announced this week, and they  aren’t exactly pouring money into Yahoo’s coffers. The company’s stock price (Ticker: YHOO) has fallen nearly 20 percent over the past five days, from its July 27 price of $17.31 to today’s $14.44 (as of this writing). Microsoft’s stock is up very slightly over the same period, from $23.11 to today’s $23.81, but a flat trend doesn’t constitute a ringing endorsement. “I was myself