Ann: Kanuka Lithium Project Update, page-138

The only way he could slander you Roo is to use the spoken word. Libel is written defamation I believe?
I also don't believe that you can defame a nom de plume however a nom de plume can defame a real person.
Defamation can be either written or verbal so you are suggesting Comanche is defaming your nom de plume character which of course can't be challenged legally. If however you were to defame Mr Brewer then that can be challenged legally and successfully which has already happened with some HC posters previously (Not with Jason Brewer though that I am aware of).
Apart from some banter though it is best not to make any personal attacks because mods take a dim view as it creates more work for them that they really don't need.

Now...ante up Roo ya chicken I will go you halves with any of my winnings!