Somebody here implied that a main quest or purpose is something for "non RPGers". Kudos for the most absurd statement in the history of this forum. Surely no small feat.
If you are referring to my comment, I said main quests don't have to hurt roleplaying, which only implies that the main quest CAN hurt roleplaying, which it can do since it is the only part of the game where you don't get to choose who you are (ie. you are dovahkin, nevarine, etc whether you like it or not.) If you don't mind the part of your personality it defines, the main quest is just another quest.
And even if I were to suggest that main quests are there for non-rpg players, how is that absurd at all? Take out the main quest and this game is almost entirely inaccessible for players from other genres...
Funny thing is the only other unique aspect of the main quest I can think of is that it is what you are told to do in game as an extension of the tutorial. Change the way the main quest starts by not telling the player to do it and magically there is no main quest anymore, just another quest line that's longer than the others...