> When disagreeing, please reply to the argument instead of calling names. E.g.
  > "That is an idiotic thing to say; 1 + 1 is 2, not 3" can be shortened to "1 +
  > 1 is 2, not 3." 

It's actually more "direct and to the point" to not call someone an idiot, a moron etc. Some other justification for his "brusqueness" is needed, perhaps being opinionated rather than accommodating; another instance of being blunt/pragmatic not precise/academic; a signal of willingness to defend his values for how to run linux (I've seen productive communities fail due to lack of this leadership); demonizing a common enemy to unite your side (e.g. Microsoft, Oracle).

It seems logical to me that abuse isn't necessary; but logic is a poor substitute for actual understanding.