> spending more time writing documentation in the internal wiki than doing actual work

I have to disagree that this isn't actual work, as long as he's documenting something important.

But this:

> organizing meetings with no purpose, where he appears to be making decisions

That does sound a bit like a narcissistic personality complex, doesn't it?

http://en.wikipedia.org/wiki/Narcissistic_personality_disord...

You could separate out the behaviors that aren't bad from those that are, and document the bad ones, then bring that to a manager and ask for some help.