I appreciate your tight, well-referenced essay. My gawd, I know how much work they take!
The mechanisms seem plausable. Often, I think I see children and parents using the identical strategies and hitting identical rocks in their lives. The tactics may include lying, offering gifts, apologizing, yelling, threatening, and any number of other gambits. It's often a pleasure to reflect back to parents who are annoyed by their own tactics in their child. (The child who forges hall passes often has a mom or dad with very similar anecdotes from their own past.)
I suspect the degree of similarity (not in looks, but in Psych Adaptations (1) and strategies) between a client and the hypnotist may create a useful synergy between them. Each person experiences arousal, familiarity, and acceptance from the other because of shared similarity. Perhaps the same process occurs in chat rooms. One of my adolescents met some 50 girls this summer on the net. He's a little bipolar and he found the lively ones (like Buss says he should) highly attractive and felt that he "had known them forever." He could eventually become an excellent therapist for the manics because of his own history and nature that pushes the clinical bounds at times.
You can pick for yourself, carefully!, the degree to which you use a learning or biological explanation for these fascinating exchanges (2). A calm mother could be useful for soothing a manic child; likewise, a calmer child should fight less with manic parents. A pattern emerges wherein behavior jumps generations. Or, it could be that some recessive genes are only expressed in alternating generations.(3) We may not be able to resolve these issues because we are inherently tied with self-selected data collected over decades.
1) Yes, Psych Adaptations vary anywhere to the north and east of Santa Barbara!
2) Despite academic traditions of tolerance and expression of ideas, many teachers seem extremely annoyed with biological explanations. If you're in school, be careful!
3) Even here we run again into the Imprinting and Linkage types of explanations!