> This requirement for temperate language or forfeit a receptive audience - I don't know.

I can say based on a lifetime of experience if you want reasonable and influential people to shut their ears to you, use incendiary language. And the reason is simple - the strong correlation between an emotional appeal and a lousy argument.

You don't have to believe me, but I encourage you from now on to pay attention to the language used and the strength of the argument.