Using the wiki spoils things. I think everyone knows that looking up game content on the internet is looking for spoilers. I only do it when I'm really frustrated, or don't care about the game... and I know it's me, spoiling it for myself. So if you keep information off your wiki, because you want to control how people play your game, then you're making a really shitty wiki. What the hell is a wiki for? To NOT provide game information? To intentionally obscure and with-hold information? No! That's very stupid.
This is a really good example of how one person having complete control over a project can fuck it up.