Fictive people don't just result from bad gedcoms, though -- they also result from frauds, some of which have been widely accepted by entirely reputable sources. Others result from name variations, misunderstood documents.
IMO, these all need to be well-documented, or, as Jilliane points out, they WILL keep recurring. And IMO, the best documentation is a fictive-person or fraudulent-person profile. Because what's needed is something that turns up in any search for that person.
I'd rather be franker, and call it that, rather than "disputed origins." Disputed origin should mean there's still doubt.
Speaking as a computer programmer who has been working with object-oriented code since c. 1986, I have no problem with a class of fictive person, as long as it's clearly distinct from the class of actual documented once-flesh-and-blood person.
So I'm with Jillaine on this -- if this person is likely to recur, then we should have a profile that documents that it's fake. Functionally, that's what will turn up at the point of creating a new profile.
I generally check to see if the fake is on most of the popular genealogy sites. If it is, I document it in strong terms AT THE VERY TOP OF THE PROFILE, as well as giving it the appropriate fraud or fictive categories.