Stating one's absurd beliefs is not the problem.

My experience communicating with you is that you've been very receptive to engaging with positions that you strongly disagree with but my experience communicating with most people is that the mere act of stating a position which appears to be absurd to them lowers one's credibility in their eyes for the reasons discussed under the heading "mistake #6" above.

The problem is expecting those statements to have arguing power (and you don't appear to appreciate this principle).

With the Aumann agreement theorem in mind I think that the mere statement of a belief can carry very slight argumentative power. But the qualifier very slight is key here and I basically agree with you.

At each point there are bound to be statements which are evaluated differently by different people, it's a simple fact to accept. Irrationality is signaled by inability to follow a rational argument, not by having a property of holding incorrect beliefs.

I completely agree.