Hmm well I won't speak to the "New Age-ness" of any of this stuff as I like to stay as far away from that side of things as possible. But I believe proving to yourself that you can have at least some control over your own dreams can provide some significant benefit. When I was quite young, about 4 or 5 years old I had this recurring dream that I was being chased though our family home by a Wampa (from Star Wars, why I had seen The Empire Strikes Back at that age is another story). This dream freaked the hell out of me as you can probably imagine. I told my mother about it and she said that I could control my dreams, that I either needed to make friends with the monster or kill him and that I had the power to do either one. I'm not sure how long after that it was, but there came a night and a dream where I did in fact make friends with this huge white monster, took him downstairs by the hand and showed him my toys. Now 25 or so years later, that was the last recurring nightmare I ever had. I barely have any nightmares at all in fact. I attribute this mainly to this experience at an early age.
So for me, I guess I would call that pretty life changing, but perhaps not in the way that others might think of when they attribute the term "life changing" to lucid dreams. I feel that there is some degree of mastery one acquires over one's own mind with these kinds of exercises. A feeling that this is my mind and I control it. That's always been pretty valuable to me.
Actually, I do agree with the nightmare control aspect.
"I either needed to make friends with the monster or kill him and that I had the power to do either one."
There is a third possibility: Let it catch you. That's actually how I got rid one of my recurring nightmares. I'd swear there was a second's pause as my brain asked itself "Uh, now what?"
I now fairly frequently get some imagery in my dreams that have the capability to spark nightmares, but they pretty much never get past the very beginning phase, because my brain knows from experience nothing bad can happen. Big scary monster with teeth chasing you? The best answer is to hop right on in. Another big scary monster with teeth inside the first one? Hop right on in again. Recurring dream involving fear of heights? Just fall. Eventually it'll all work itself out.
Looking back at it, I guess that's kind of what I did too, although not thinking of it that way. To this day I can remember the scene in my dream. I stopped at the top of the stairs that went down into our basement, turned around and let the monster walk up to me. I can't remember if I said anything, but I do remember holding my hand out and taking his hand.
I now fairly frequently get some imagery in my dreams that have the capability to spark nightmares, but they pretty much never get past the very beginning phase
That's pretty much how I feel as well, except I wouldn't say frequently for me. Occasionally I'll get imagery that is kind of nightmarish, but it usually doesn't seem to escalate beyond a certain point.
Facing one's fears, be they real or imagined usually has some value, in my experience.
So for me, I guess I would call that pretty life changing, but perhaps not in the way that others might think of when they attribute the term "life changing" to lucid dreams. I feel that there is some degree of mastery one acquires over one's own mind with these kinds of exercises. A feeling that this is my mind and I control it. That's always been pretty valuable to me.