You wrote you didn't like this, Jim; though you were inclined to be sympathetic with the statement of the argument "up 'til then".
When I read this piece for the first time, instantly (just as you did), I flashed on the problem of brain-to-brain trasnmission, as presently described by state-of-the-art science. Yet suffice it to say that presently the public record reports a vast variety of "brain experiences" that cannot be explained at all by present scientific methods.
Thinking the problem through further, the man did say "sign" is as valid a mode of communication as language, writing, et al. He hasn't shut the door on your concern at all.
I hope we can explore such questions on this thread, and that you would be willing to contribute your insights.
I just popped in to this thread, so I can't say if it's been discussed yet.
All I can say to this is, both my identical twin sisters and my identical twin cousins, have described experiences where they somehow knew that something was up with the other twin, and whether it was good or bad.
IF there's anything to this theory, then we'd have to surmise that brain structure would have something to do with how we interact with this UTF. Brain-to-brain transmission would be recognizeable to us only if our brain interacted with the UTF similar to the other brain -- which I think would be more likely for identical twins than for anybody else.
A test of the theory might thus be performed using identical twins, perhaps looking to see whether there were any correlation between the experiences of one twin, and the brain waves of another. I'm thinking young twins would be the best subjects, as there has been less time for "nurture" factors to interfere with brain responses.
(It appears that one version of this study has indeed been run, with apparently positive results.)