Characterizing it as you have, it makes me think that the LBF, if we can refer to it that way, should have a trademark affixed to it, as common as its use comes across!!!! I think that would've have been rather difficult for him to pull off, as all the bridge staff knew about it and came unequivocally to believe it, even T'Pol, as would just about the entire crew, one would have to imagine, given what they directly experienced. How would he have gotten everyone to keep quiet about it? Taken a blood oath? OK, I'll bite on the first two, but I don't know where you're getting any substantiation for Mitchell's case. I don't recall any canon citation that such happened. Why would he have done so? I might argue elsewhere, that he could have to have hidden his culpability in the incident, but I doubt that's what you mean. Mitchell was cited for dying in support of doing his duty, though I suppose the exact circumstances might have been obscured. But if for no other reason than making it known to Starfleet the dangers of encountering the Barrier, I can't imagine Kirk being so irresponsibly lax and capricious. Again, what woud be the purpose?