That all depends on how you want to define 'original'.... similarly, the whole Will Riker transporter duplicate storyline was a similar deal, wasn't it? Neither was the 'original', one just got luckier than the other.
I liked the double-John act... obviously, you knew from the get-go that one was dead... after Talyn-John hooked up with Aeryn full-time you DEFINITELY knew he was dead, but still, managing to draw it out for most of an entire season isn't something most series would do... an episode or two parter sure, but most series don't have the creative capacity...
And yet, it doesn't feel cheap or a cop-out when Talyn-John dies. It really feels like John Crichton made the heroic sacrifice, and when Aeryn and Moya John meet up, it still chokes me up seeing the anguish on her face when she thinks to herself that this
John is the fake.