[yboris]

One great technique for understanding others (and often as a bonus also showing them they don't know what they are talking about) is to simply ask for the mechanism they are describing.

So when someone is in favor of policy X, ask them how X accomplishes the goal they are in favor of -- what is the cause-effect chain.

This (at least according to psychologists' research) usually makes people more cognizant of the gaps in their understanding, and also more receptive to alternative solutions or explanations.