Why does it matter if it is true? Look how many souls it saved?
My kids participated in an anti-drug program in school. When i got ahold of the material, i found that a lot of it was exaggeration.
I could be happy that they oversold the dangers and kept kids off drugs, but i worry that when they learn the facts, they'll feel they can't trust/needn't heed ANY of the material from the program. They may overreact to being lied to.
I knew several Mormon kids that went to college, discovered that sex didn't cause VD four times out of five, nor pregnancy six times out of five, that beer didn't cause immediate permanent retardation, and went a little crazy in indulging, to make up for lost time.
If someone was 'saved' by a story they later find out was a lie, i would expect some to have drunk enough Kool-Ade to repeat the 'it doesn't matter, it saved me' line and 'God's so wonderful he sent a LIE that i might find the truth.'
Or they might wish they had their tithes back, that they hadn't broken up with that girl who had no gag reflex, that they hadn't turned their dealer in...