The atheists and Christians were told to be honest when writing their own responses. So they shouldn't have been trying to game it in this way.

"Honest" leaves a lot of wiggle room. If I were trying to write my honest atheist entry, what do I emphasize? That I hate scholastic philosophy and think religion set ethics back five hundred years? Or how I love C.S. Lewis and G.K. Chesterton and find many religious works to be among the most sublime creations of humankind? Both would be "honest".

Even if someone genuinely sets out not to present themselves at all, I still would expect presentation to be their main concern. There's a certain class of things which are impossible to do naturally. For example, if you try to count your natural respiratory rate, you will fail miserably; the fact that you're thinking about your breath immediately shifts it to consciously deciding what it is going to be. In my case, it makes it slower than normal. I can try to then consciously adjust by speeding it up, but since I don't know how much to speed it up, attempting to breathe naturally is basically just me trying to fake my natural breathing rate, probably badly.

I think self-presentation attempts of this sort raise some of the same problems.