This has gone into a tangent from the topic that started this, but to bring this back to William's point, that's exactly what I think he's saying about the original main characters.  The further out you go from their original intention and depiction, the more off model you go into variations of their initial depiction, the less appealing and popular they are.  Neil Gaiman noticed this when the Hollywood movies started coming out about ten years ago with the first Hulk movie for example, when he said that it's interesting that there seems to be a correlation between when the movies don't do so well and the director taking characters away from their fundamental characterizations.  Maybe this isn't true in every case.  But it might be accurate most of the time.  

The Hulk is an interesting case because I wonder, even if the comic book market were more mainstream and the hardcore fans weren't the center, would the original Hulk be more popular than the intelligent Hulk?  Peter David wrote about that version for a really long arc that breaks the principle William described here.  What if a later version of a character is more popular with a large audience than the original?  Should the original still be adhered to?