A lot of initial fan backlash on this trade. I don't have a huge problem with this trade and may actually like it. It is clear from the Latos and now Rizzo trade that a top middle infield prospect that is close to ML ready is just not available. There is such a huge drop in talent from guys like Machado and Profar to the next level of middle infield prospect. Some fans wanted Wade Davis from the Rays. Why? I wouldn't put him ahead of Anthony Bass on the depth chart.
The biggest argument against this trade is from a "value" standpoint. Clearly, the Cubs valued Cashner very highly or Cates would not have been added. Many fans feel Rizzo has far more "value" than Cashner.
What I like about this trade is that the Padres get a reliever that should be very effective at Petco in 2012 and still control him for several more years as they work to figure out what Cashner's real future is. Cashner has solid stuff and a plus-plus fastball. His control has been improving each year and now he has a chance to work with Black and Balsley. The Padres essentially are getting a solid late inning relief guy with elite starter upside. The one thing the Padres deep stable of pitching prospects has lacked is an "elite" upside pitcher that is ML ready or close to ML ready. You could make an argument that Cashner has the best "stuff" of any Padres player or prospect. This represents the beginning of the next "phase" in the Padres future... aquiring and drafting "elite" upside players. I think you will see the trend continue in the 2012 draft. The days of drafting safe college players are behind the Padres.
Byrnes, IMO, has done an excellent job of continuing the movement for the future while simultaneously putting together a team in 2012 that may surprise. Cashner fits both the "win now" and "build for the future" scenarios.
I realize I may be in the minority, but they had the depth to take the gamble.