A white knight is not at all similar to a troll. A white knight genuinely believes in what he says and does. A troll will do or say anything for the biggest reaction, independent of what he actually believes.
In context of this thread, they are.
DoctorMog knows **** well this game has issues and deserves at the very least, some of the beating it takes for being horrible. He would be white knighting if SE were is a position where they needed a defense, but they don't. The reason it isn't necessary is because SE already stepped up, admitted that the game is in a ****** state and apologized. They aren't even defending the game (since November), yet some people feel the need to step in and do it for them.
There is not a noticeable difference between a knight and a troll here because there is no need for a knight. SE is waving the white flag and doesn't need defense. The 'knights' are attacking the OP, not defending the game. The 'trolls' are defending the OP. Bizarro troll says hi.