Ah, I see. First off, I can only repeat what Rhewin and the others already said, the SC is not acting against you. If you see a DS in your dream and you don’t get lucid, well, then it’s your fault. It shows that one’s awareness isn’t high enough, the SC even was so nice to give the dreamer an obvious sign that he’s dreaming, and he missed it!
I think there’s a difficulty regarding the definations when discussing about things like this. (Sorry, I bet I’m writing about stuff you already know.) You, I, every human consists of the id, ego and super-ego. The id is unconscious while the ego and super-ego are partly unconscious, partly conscious. When you say that the subconscious fights with the conscious then this would mean that the ego also attacks itself, which would be pretty paradoxical.
Alright. Now you might say that if it’s not our SC which prevents us from becoming lucid, then it is the id. Maybe id wants to sleep and is thus fighting against the conscious part of our mind which is going to get lucid, to “wake up” a bit. Well, but what is this “us”? Neither your SC nor the unconscious part can prevent “you” from getting lucid, because it is a part of you!
Also, the id is quite wrong when it thinks that the result of getting lucid/aware = waking up. Maybe it has to learn this fact since it is something entirely new.
Now about your question/theory about FA’s which just crossed my mind: Freud said that the ego is kind of out of action when one’s sleeping. This means that the defence mechanisms it usually maintains against certain parts of the id are also enfeebled or not existent. When you gain awareness, your ego gets more active again. Now, your id says, Ah but no, I don’t want to wake up yet! It is trying to suppress the ego, the awareness. There are a few possibilities right there:
1: You gain more awareness. Your ego is fully active and can defend the id so that you are lucid. The id might be pretty satisfied with this afterwards! It kills two birds with one stone: The dreamer is still asleep, and in the dream there is no reality which keeps the id away from doing what it wants to do, so many needs of the id can get satisfied in a LD. This might result in the id not fighting against the ego the next time it becomes active while sleeping.
2: Your awareness is too low. Your ego loses against your id and you keep on dreaming a ND.
3: Something between number one and two. Your id wants to continue sleeping (the dream goes on). Your ego is active and not willing to lose against the id (the dream is a LD). Basically, the ego doesn’t want to fight, it only tries to maintain a state of balance between all those components in order to make the best out of the situation. Your ego is now weak and it wants to find a compromise even more. And what is this? You said it in your theory, it’s the middle ground, a FA. Expectations (as already said multiple times) are playing a huge role here, too. Both your conscious and unconscious parts know that normally aware = awake, and because the dream world is created mainly by your unconscious parts and the id wants to keep on dreaming, the effect of this compromise is a dream where you wake up.
I’m not sure if this has already been said, but many LD’s result in FA’s instead of waking up. One more proof of the power of expectations.
Sorry for the wall of text, I hope at least some parts are helpful and/or interesting…