The idea that someone was once a genuinely knowledgeable evolutionist, and then somehow switched to creationism, is about as likely as someone who was once a deeply committed Christian bible scholar, who then gives it up and converts to voodoo. It just doesn't happen.
I think some missionaries used to "go native" but we can be sure no true Christian ever did.
It does happen both ways. Since they started teaching evolution, there has been a snowball effect on the youth turning from religion in general as evolution calls their parents' religion a lie. That's why it's in the schools. And the result of that is discernable in the historical data showing the decline of morality and it's affect on society since the 1960s. The lie is so pervasive that the damage is widespread. The extent of the damage is matched only by the anger of those who finally realize they've been lied to and after examining all the facts. Once one reaches that point, they have two options, God or their own path. The choice doesn't change - the perception that the choice exists does.
The real impact is easy to see. If you can convince people that God's a liar or that scripture is a lie, you can get by with anything. Cause those people aren't going to hold you to a standard if you've convinced them (however wrongly) that their standard is a lie. Now you can get by with murder - literally, because everything then becomes situational and relative. To Hitler, Aryans needed more room to thrive and the jews posed a problem as being the "chosen" people when Aryans were supposed to be the "chosen" people. In a moral relativistic society, this becomes all the reason in the world to commit genocide.. just as "my life will be impacted negatively if I have this baby" becomes all the reason needed in the world to murder a baby - to the glee of the liberal who wants to have unprotected sex with as many women as possible with no responsibility, then legislate a tax on all of us to pay for that damage.
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