I'll try to give some examples of what I think.
In response to
"McEwen now says problems are over!"
Wrong:
"His mum promised to help him with the t-shirts?"
Right:
"Based on previous statements I have no confidence in McEwen anymore."
In response to:
"BBRV says they are not interested in the Amiga trademarks."
Wrong:
"And yesterday they wanted a license? ******* liars."
Right:
"I find this inconsistent with their previous statements, could anyone
explain?"
In response to:
"Alan says the A1 has sold more than the Pegasos."
Wrong:
"Yeah, like he said there were no bugs in Articia.."
Right:
"Does he tell what number of Pegasos sales he's comparing to?"
In response to:
"BBRV says they don't consider Amiga to be a competitor."
Wrong:
"Uh-huh? Why then do they spend all their time spreading FUD against
Amiga?"
Right:
"From what they do, it seems to me like they are competing with
Amiga."
Avoid sarcasm if you know it's going to be controversial.
Don't respond to one question by bringing up another, old question.
If you can't defend a particular action/statement from "your side",
don't try to switch subject. Concede the point and remark that in
total, this does not change your position.
Don't treat your opinions and theories as facts, insert "in my
opinion", "it seems to me", etc, when you expect others to have
different impressions of reality.