But that doesn't mean that you can't demonstrate its extreme to the nth degree unlikelihood; to which those with their fingers in their ears will pay not the remotest attention! Grrrr....

Which is what I've been saying ad nauseam. Actually, I'm not sure that "demonstrate" is quite the right word there. I can make the case, for example, that the likelihood of God's existence is, once you've applied all rational means to the argument, vanishingly small, but, by so doing, I haven't really demonstrated anything save my ability to make the point. We genuine atheists are very 'umble, you know.