Are they afraid to be labeled clinically insane if they claim to have met Christ in the flesh?

Wouldn't real stories of meeting Christ in the flesh bolster faith in His gospel and strengthen Church members?

So why do they keep hush-hush and walk back on this all the time?

The whispered suggestions that they have seen Jesus in the flesh is enough to sustain members' belief in this. I would imagine if you asked, a large percentage of members would assume that this is the truth ("Well, of course the prophet has met with the Lord. It's too sacred to talk about, though." Never mind Joseph's [spurious] claims that he told almost anyone and everyone about his experience.).

Actually, has anyone AFTER Joseph claimed to have trafficked with Jesus? I know the Q12 have toned down "special witness of Christ" to "special witness of the name of Christ" or some other garbage, just to avoid being pressed on the issue.

Gordon B. Hinckley, San Francisco Chronicle, Sunday Interview, April 13, 1997, by Don Lattin

Don Lattin: "And this belief in contemporary revelation and prophecy? As the prophet, tell us how that works. How do you receive divine revelation? What does it feel like?"

Gordon B. Hinckley: "Let me say first that we have a great body of revelation, the vast majority of which came from the prophet Joseph Smith. We don’t need much revelation. We need to pay more attention to the revelation we’ve already received. Now, if a problem should arise on which we don’t have an answer, we pray about it, we may fast about it, and it comes. Quietly. Usually no voice of any kind, but just a perception in the mind...But in a still, small voice. Now that’s the way it works.”