A wise conversationalist avoids topics that demand tsumi. Polite listeners may feign a courteous interest in things that you are saying, but that is not what you should try to achieve.

Furthermore, topics that demand tsumi are rarely cheerful.

Thus, you might want to tell others about the new computer that you just bought, but not about your suffering when the store did not deliver what you expected.

I know what you are thinking. You want to raise people's consciousness on an issue that you consider to be important. That's a good way to convince yourself that the tsumi is worthwhile, but no intelligent listener would buy it.