The Move That Could've Helped The Oilers The Most...

Previously, I asked:  "If you could go back in time and undo just one move that the Oilers' franchise has made since 2006, which transaction would you undo?"

The answers were great fun, in a masochistic sort of way, and if you're an Oilers fan, what other way is there?  This time around, we're going to flip that the other way.  Beginning with the unwinding the Oilers via the Chris Pronger trade, which single move, in your judgement, would've helped the Oilers the most?

If you could go back in time and perform just one management, roster or draft move that the Oilers' franchise failed to make since 2006, which transaction would you execute?

The move must be one that exists in the reality of this dimension, meaning, you can't pull out a HFboards trade proposal and move superstars Cam Barker and Darcy Hordichuk for Ryan Getzlaf, so unless it was a trade rumor acknowledged by someone like Bob McKenzie, trades are out.