Tyson Foods' (NYSE:TSN) stock is now efficiently valued. You should sell it unless you think you are deft enough to make a few more dollars selling it into price momentum from better technicals (Zack’s just recommended it) or earnings momentum (Bank of America-Merrill Lynch analyst just upgraded TSN based on EPS estimates above long-term normalizable earnings and BMO recommended it last week). In October 12 2012's buy recommendation I wrote: Tyson's stock fell from near $21 in May to $15 in July as the market over-discounted the effect of the drought in the US Corn Belt.  Higher feed pricing ...