I think Locke was lying when he said he took Christian's form.
maybe
playing devil's (smokey's?) advocate:
Why would he lead Candidates to water and help Jacob by keeping them alive.
theoretically, it was to keep john locke alive, whom he could later trick and take over. and, because locke was a candidate, that'd give smokey access to jacob.
Christian appeared off island on the frieghter and in Jack's waiting room in LA which the Smoke monster obviously can't do.
the appearance in the hospital coulda been jack's drugginess at the time. the appearance to michael on the freighter... i dunno about that one.
In that early episode Christian lead Jack to the caves and then dissappeared. This goes against Smokey's MO as seen in the Richard episode and with other characters. Why not talk to Jack and say "hey this weird island has a big bad mean old man keeping you from being rescued." At that point in time Jack had just been there a few days and would be easily manipulated.
i think "ghosting" as your just-died father is a little easier to accept (in a giant "relatively speaking" context) than noting there are giant, earth-altering plans in place that jack is to be a pawn of.
I don't think it's an oversight in the writing, more that he was lying to Jack to try and win him over.
mebbe. but, then again, smokey
did know that christian's ghost lead jack to the water at the caves. if it wasn't him, he at least got that info from recently-deceased-and-ghosting christian.
