There was one deadline deal I did not understand last year, with the Pittsburgh Penguins sending promising defenseman Simon Després (a potential #2-3 D) to the Anaheim Ducks for Ben Lovejoy (a #6 at best).
Sometimes, teams need to trade talent to acquire grit - that's fine; in this case, however, it was NHL-ready talent for grit that wasn't even good enough to dress every game. Even GM Jim Rutherford admitted to regretting it just a few weeks later.
Després is tall at 6'4'' and strong at 225 pounds, but he isn't overly physical; he doesn't need to be, because he has the speed to make plays and correct mistakes without needing to make the violent checks a stay-at-0home defender would.
He even has he physical skill-set to develop his offensive game - all he needs to find out is when to move up-ice with the offense and he'll be a very valuable piece of the Ducks moving forward, in the same vein as Cam Fowler.
Here's a nice card of his in the Pens' white (away) uniform, from Upper Deck's 2011-12 SP Authentic set (and Future Watch sub-set):