I'm really surprised this thread has gone this long without anyone bringing up Magnussen telling Hulkenberg to "suck my balls, honey" on national TV while chatting with Buxton; after Hulk congratulated him for yet again being the most unsporting driver.
Without missing a beat and a smile on his face ... Suck my balls, honey.
I guess it didn't dawn on Hulk that Mag didn't give him any room, as a bit of retaliation for when Hulk cracked into Grosjean which lead to the retirement of his car. Regardless of the penalty the stewards imposed on Mag ... Hulk could've backed off ... he pressed the point and went off track. Fairly simple. I imagine the stewards gave Mag the penalty because it was highly likely it was a retaliatory move, more than simply owning the corner.