Coffee Addict’s point was that even thought they were covering up for themselves (and could have used the Shalom takes precedence over Emes argument) they still made sure not to tell an out-right sheker. He was trying to say that when you are covering up for yourself, you are not allowed to lie.
I argued that they were still being deceitful (just less so).
You argued that we can’t learn from what the shevatim did, because maybe they were wrong just like they were wrong about Mechiras Yosef.
I am saying that we can learn from them because even though they may have been wrong about Mechiras Yosef, there is no reason to believe they were also mistaken when it comes to the halachos of lying.
So I’m not sure what your point is. Is your point that if someone is the kind of person to do something wrong, what he says doesn’t matter? If so, I don’t get your point. Nobody is perfect. Just because he made one mistake, he doesn’t have to make a second one by lying. Also, he might not have done something that was objectively wrong – it could just be that he knows someone will get upset about it.