They drafted well. Took a gamble and it paid off. Good for them. Still, I would do that trade every day of the week if I'm the Oilers. Kulak has been a perfect fit and has exceeded expectations by a mile.
For the rebuilding Habs, it made sense to get a pick, a pick that very well could have been a bust too. For the contending Oilers it made sense to get a Legit NHLer with still untapped upward potential that could fit in the Cap on the cheap. I'd typify it as Win-Win trade, which is the goal of all trades.