Mental models are often unstable and do not support hypothesis testing well unless they have become rule or skill-based. Identical information may have different meaning depending on context. Context is as important in cognition in determining behaviour. Communication between operators is extremely important, and can both help and hinder reasoning. But it is central to real decision making.
Mental models have a variety of forms which support skill, rule and knowledge based behaviour.
Almost the only kind of reasoning which is not seen in real settings is that most commonly investigated in basic research in cognition, i.e. deductive reasoning on logically closed problems such as those investigated by Johnson-Laird. Bainbridge, L. 1992. Mental models in cognitive skill. Bainbridge, L. 1974. Analysis of protocols from a process control task.