It wasn't really meant as a joke, but more to show your argument wasn't valid.
You implied that because Revan said he was from Delaria (sp?) then that "obviously" meant that's where he was from. Using that logic, then it's just as valid that Revan is a Wookiee from Kashyyyk because he said so.
In other words, there's still no proof that Delaria (sp?) wasn't just an implanted memory, rather than his actual homeworld. What Revan said alone is not proof.