You're completely right, of course; however, no, I don't intend it as a scientifically rigorous experiment. Actually, I'd like to see what happens when people whose most controversial opinions are NOT worthy of explicit disdain (such as racism or sexism) discuss their controversial opinions. Hubski is implicitly not a welcoming community to people who seek to offend or who are seeking microcosms online where opinions considered repulsive in the mainstream are heartily seconded, thirded, and more. (See: r/MensRights) So, it's not an experiment comparing Hubski and Reddit, necessarily. It's an experiment comparing a context explicitly welcoming to racism, sexism, classism, and so on and so forth, vs. the question of controversy posed in a context explicitly unwelcoming to the same.