Is this general advice that you would also give to someone who, say, expressed an interest in learning about quantum gravity, or do you think there something especially harmful about political beliefs?
I wouldn't be very surprised if political beliefs were especially distracting, but non-political (well, non-overtly-political) beliefs & topics can also be good at consuming attention. Bonfires of attention I've seen blazing away on LW include the Sleeping Beauty problem, how to interpret QM, and how to interpret probabilities. (Some political beliefs at least have the merit of being testable!)
Also, it seems there should be ways to combat privileging the question other than abstaining from political belief entirely. That seems like a rather radical (and somewhat defeatist) solution.
And one easier said than done. Whenever someone tells me they're apolitical or refuse to hold political views, I brace myself for the inevitable accidental unveiling of their non-existent politics. (This doesn't just apply to people I have extended personal interactions with. Look at Philip Larkin!)
So you're playing the credence game, and you’re getting a pretty good sense of which level of confidence to assign to your beliefs. Later, when you’re discussing politics, you wonder how you can calibrate your political beliefs as well (beliefs of the form "policy X will result in outcome Y"). Here there's no easy way to assess whether a belief is true or false, in contrast to the trivia questions in the credence game. Moreover, it’s very easy to become mindkilled by politics. What do you do?
In the credence game, you get direct feedback that allows you to learn about your internal proxies for credence, i.e., emotional and heuristic cues about how much to trust yourself. With political beliefs, however, there is no such feedback. One workaround would be to assign high confidence only to beliefs for which you have read n academic papers on the subject. For example, only assign 90% confidence if you've read ten academic papers.
To account for mindkilling, use a second criterion: assign high confidence only to beliefs for which you are ideologically Turing-capable (i.e., able to pass an ideological Turing test). As a proxy for an actual ideological Turing test, you should be able to accurately restate your opponent’s position, or be able to state the strongest counterargument to your position.
In sum, to calibrate your political beliefs, only assign high confidence to beliefs which satisfy extremely demanding epistemic standards.