I think that it workable, however, how do you tell people to go out and do that? Wikipedia is unlikely to tell contributors to go off to somewhere else to contribute; it makes little sense.

I was thinking something like GitHub, create an account and you can write your own page's or fork other pages, modify them and do a pull request. You're forked version survives regardless of what happens to the pull request.

I do think that is a good idea, however, trying to tell historians and bio-peepz and whomever else that is not a programmer how to do this, and the reasons they need to do this in the first place, will end in failure. Adding more steps in that process will decrease use and contributions.