I don't think students tend to be particularly shortchanged with respect to that sort of lesson by the current system though. Most students are aware of who the top students are, and that the top students are more reliable in their areas of expertise than the lesser ones.
Should they defer to the top students in matters outside of what they know to be those students' areas of expertise? Not necessarily; a lot of smart people are not particularly good at getting right answers outside their areas of expertise. For a not-so-smart person, simply trusting that a smarter person knows what they're talking about on any given subject, even when they don't know that person to be an expert on the subject, is not a very trustworthy heuristic.
Trusting people who're more expert than you in a particular field over your own judgment in that field is something that most students already learn. Being unable to assess who's more expert in domains in which they're not well trained is natural and probably unavoidable, and students can't be trained to be expert in everything.
As a teacher, I wonder if it is possible to instill this skill into students the skills of rationality and critical thinking. I teach the third grade, and it is not immediately apparent how to apply this with my own class.
The problems I foresee are as follows:
In the sequences, it is suggested teachers should drill into students words don't count, only anticipation-controllers. How practical is this for an elementary school level? Also appreciated would be any ideas or experiences on how to do this, or how to combat the above problems. Hearing from other teachers would be excellent especially.