What advantages does a control room offer?
Well, I use my control room to stage my plans for world domination. It makes my job very easy because it is the hub of the activity in my empire. I can control many aspects of my empire from the ease and comfort of my control room. Hence the word "control".
The biggest advantage is that your listening/mixing environment is separate from your tracking environment. If you can get good sound isolation between your control room and your tracking room, you can listen to your source material as the player plays and hear what it sounds like in the monitors. You can hear the effect - better or for worse - of moving a mic a little bit. Being able to do this in real time instead of move the mic, record some, play it back, move it again, record some, play it back, move it again.... is a real advantage.
Oh, alright. That makes sense. This thread can die now.