Re: Wait a minute.
In my own experience, and in my historical research, personal memory is more fallible and mutable than the written record—even the online written record.
Of course Peter David's policy applies only to his own copyrights; he doesn't get to decide on other people's property. And I don't see anyone claiming he did "change his position on scans in general." Rather, some commenters had changed their memory of that position to one he specifically disavowed.