Sometimes a Wiki Champion can over do it. If they don't trust other people to contribute to the wiki, they may feel the need to step in and make all of the edits and additions themselves. When that happens, no one else on the team ever becomes comfortable using the wiki, because it always seems like the Do it all's property.
If you find someone saying, “Oh, here. just let me do that for you,” they may be going overboard. The more experienced team members need to be willing to tolerate some messiness, or some ideas that they may not agree with in order to let the rest of the team become comfortable contributing to the wiki, and feel the sense of ownership they will need to make the wiki successful.
Don't let the do-it-all take over work from other team members. Explicitly ask some less comfortable team members of the team to contribute. And if those team members need help, sit with them while they create their pages. Offer suggestions, but let them drive.
Take breaks, slow down.