I also don't understand, but I know that Jimmy Wales knows a little more of wikis and collaboration than me. I'd probably say that an editable encyclopedia wouldn't work. Now I consider it one of humanities greatest feats.
Actually, if I'm remembering the details correctly, Wales also didn't think it would work. Wikipedia arose as an offshoot of Wales' Nupedia. I don't think Wikipedia was his idea, and I believe he was opposed to the idea of something that was freely editable.
Go for it, Jimmy!