User WikiNames and FAS

A thought about FAS2 and wiki integration: Since wiki editing is tied in with FAS2 and CLA signing, it'd be nice to integrate them nicely (click-through CLAs are already implemented in FAS2), but one annoyance is that WikiNames do not generally match usernames. Other than for (weakly) connecting wiki usernames to FAS users, is there any particular reason that we're going with the FirstnameLastname convention? Would it somehow be "bad" for users to have the same username for FAS and the wiki in the future? Thanks, Ricky