In Dec. '11 the Cubs were also shopping a solid 28 year old starter with two full seasons of team control remaining. One rumor had Garza going to Yankees for their top 2 pitching prospects, huge RHP Dellin Betances and diminutive LHP Manny Banuelos. Both were considered top-50 MLB prospects going into '12. The Yankee fan forums erupted in incredulous outrage, "...TWO projected TOR pitching prospects for Matt F'ing Garza???" Obviously the rumor proved false and the trade never happened. Garza stayed a Cub and battled some injuries. When healthy he continued being what he always was, a solid mid-rotation starter showing occasional flashes of greatness. Betances and Banuelos? Both regressed. Banuelos reached AAA in '12 but struggled. He averaged less than 5IP in his 6 starts before undergoing season-ending TJ surgery. He missed all of 2013 and is questionable for the start of 2014. Betances flopped as a starter and his command issues followed him to the bullpen. He's bounced around and he's nearly out of options. The moral of this story is obvious. Could B & B bounce back and reclaim their earlier projections? I suppose. If the Yankees could turn back time would they still reject the trade? You decide.
This analogy isn't perfect. Shark is cheaper and presumably more durable than Garza. On the other hand Sanchez reportedly suffers from poor mechanics which hurts his command and could jeopardize his arm. Stroman is downright small. If Toronto offers-up both pitchers should the Cubs accept the trade? You decide.