Beef packer margins are on a one-way trip to a very unpleasant place and despite a brief rebound last week, remain absolutely dismal. Packer margins improved $66/head last week thanks to a massive surge in beef values and modest fed cattle gains, but profits were still horrid at -$237/head, which is the fourth-worst margin in WPI’s model history. The situation doesn’t look good going forward with beef prices set to seasonally decline in the next few weeks while incredible fed cattle basis levels point to continued cattle pricing strength.  Feedlots saw mixed profits again last week ...