NLP consists of a number of models, and then techniques based on those models. Thinking is tied closely to physiology. People's thought processes change their physiological state. Sufficiently sensitive sensory acuity will help a communicator fine-tune their communication to a person in ways over and above mere linguistics. These actually appeared in Erickson's work and the work of others, though Bandler and Grinder took them much further.
Different people seem to represent knowledge in different sensory modalities.
Their language reveals their representation. Often, communication difficulties are little more than two people speaking in incompatible representation systems. This is a set of linguistic patterns Milton Erickson used to induce trance and other states in people. Eye accessing cues. When people access different representational systems, their eyes move in certain ways.