I deal with disassociation in waking reality, tons of feelings of "derealization", which has nothing to do with lucid dreaming nor was it induced by lucid dreaming. However, lucid dreaming opens one's mind to the endless possibilities OF the mind. It requires a deep amount of awareness and self-awareness and questioning reality. I can see how someone who hasn't dealt with some derealization can experience a small degree of such in waking reality, but not enough to induce a psychotic state or have lucid dreaming be "dangerous".