> many [other places on the internet] have a vastly higher calibre of political discourse than HN.

Can you (or anyone) point us to these? Not being sarcastic, but also somewhat skeptical - I've never encountered another public forum of HN's overall quality.

I think the metaphor about the geology lecture is misleading - HN isn't a lecture hall, it's an exhibition hall, and if the only criteria for something being an exhibit is a capacity to intellectually stimulate, then I don't see why political discussion should be precluded.