WUT IT IS DV, I have a few questions pertaining to lucid dreaming.

1.) What holds people back from fully controlling their lucid dream? I've seen alot of posts where people realize theyre dreaming, however they can only partially alter things in their dream. For example people have mentioned they have trouble flying, cooperating with DC's, finding people, shooting fireballs, etc. I would think that the only impediment would be actually realizing that your in a dream, and then you can alter the world at will?

2.) From peoples experience, do crystals such as amethyst have a noticeable effect on lucid dreaming? And if so, is it likely just a placebo effect or is there tangible evidence that these crystals are beneficial?

3.) Anyone know the scientific reasoning as to why cannabis has a negative impact on your ability to lucid dream? I would initially think that the opposite would be true. At least with sativa-based strains.

Thanks guys.