.it seemed to really have no point to me.the storyline had clearly shifted to quentin's haunting of collinwood.that's where all the attention was being focused.the storyline with barnabas going back in time to save vicki came out of nowhere and didn't really change anything in the present or affect the rest of the story.at the end of the day vicki was still back in time.
The reason that excursion took place was that the fan mail demanded it. The fans hated that Vicki had just disappered back in time and demanded an explanation for what happened to her there. So, the writers put together the three and a half episodes in the middle of Quentin's haunting to tie Vicki's story up with the neat little bow of she and Peter supposedly going off to live happily ever after. And the reason Alexandra didn't return to play Vicki was in part because she was already too pregnant by then and didn't want to return.
All that being said, though, one of the reasons that I find what we learn of Vicki's fate during Leviathans to be such a slap in the face is because of how they'd gone to the trouble to tie up Vicki's story so neatly, yet when [spoiler]Dennis Patrick wasn't available to return as Paul Stoddard so that Paul's ghost could haunt Jeb (which had been the original plan - and which made perfect sense), they decided to have Peter (of all people
) haunt Jeb and they needed a reason to justify why Peter would haunt him, so they came up with a backstory that Jeb had conveniently been responsible for Vicki plunging to her death from Widows' Hill - which not only robbed the audience of the happy ending the writers had taken pains to give the audience - but it made absolutely no sense for Jeb to have been responsible for anything in 1796 when he merely existed as essence at that time.[/spoiler]
But then, don't get me started all over again on that wacky plot development because I've already written ad nauseam about how senseless it all was.
