I present Exhibit A, the lyrics of The Stowaway (Ooh, that rhymes! Shut up, Ten, who let you in?)
Beg borrow or steal, I’ll find a way
to be with my love upon Christmas Day
And I’ll run and I’ll walk, I’ll cover the ground
Next Christmas I’ll see you, I’ll be around
In general, the Christmas song lyrics have been spot-on. These suggest the Doctor making a real effort to get back to Rose, in the spirit of the original romantic quest narrative. Aesthetically, that works quite well. It looks as if, according to the S4 set-up, Rose is taking all the initiative getting back to him, and probably for reasons other than wanting to be with him (Quite right too). Fine, but that does beg the question of whether he wants her back, and whether she knows he wants her back. So having him fight his way back to her could be a nice way to balance things out.
What we might well see is a scenario playing out which makes it difficult, but not impossible or immoral for him to get back to her. For example, Donna might give her life up to save the universe or meet some other terrible fate – and he chooses to remain behind for a while, either to tell her family or to reverse time and give her another chance (this would, of course, fit in with the drop-off to WIlf that people have seen being filmed, when he tells him “She won’t remember a thing” and then appears to return alone to the TARDIS).
We know CT is leaving, and that RTD doesn’t like to do companion death. At least, that’s what he said pre-Doomsday and it makes sense. And I’m convinced that, no matter how great his love for Rose, the Doctor would feel a huge responsibility to Donna and a very real affection for her. He’d probably do right by Donna even if it cost him his happy ending with Rose. That is totally IC for him – it doesn’t mean he loves Donna more. It’s just him.
However, if the two universes are actually merging, there might need to be other reasons why Rose wouldn’t immediately go with the Doctor. One interesting one could be that she’s reunited with Jack and wants to find out just what happened post-POTW. Since the Doctor would rather chew nails than give her a straight answer on that one, and Torchwood is two men down, Rose might elect to stick around in Cardiff for a while and rebuild that relationship a bit. I’d really love to see that happen. Jack has been conspicuously absent from all the S4 trailers and speculation generally and that so needs to be addressed. After “Utopia” it’s obvious he cares deeply for her, and he knows she was the unwitting cause of his little problem. Both were enough of an issue with the Doctor to make him wait 140 years, so surely he’ll want to catch up with Rose?
Or it’s quite possible that everything is lined up for the Doctor to return to Rose, maybe crossing the Void, when the TARDIS is invaded by Cybermen or something like that.
I haven’t actually seen this possibility discussed much in fandom. Everyone seems to be focussed on RTD wrapping things up, but in fact he isn’t going at the end of S4 – he’s writing the specials. Imagine the impact of a huge D/R reunion on Christmas Day! Although Billie wasn’t around when the Christmas Special was being filmed, this could easily be accommodated if they spend most of it apart. The beach scene that caused so much squee a few months back, with Rose waiting for him (and it did seem to be older Rose, not a flashback) and him in the blue suit, could in fact be the end of the Xmas special. No reason why they couldn’t pick up a few shots while she was known to be filming S4.
Another intriguing little news tidbit concerns the December trio of DW novels. One called “The Story of Martha”, one with Donna and a solo Ten one, the writer claims on DWF. Okay, no Rose, but the change of policy suggests they are very definitely drawing a line under Donna (whereas they went on with Martha books long after she’d left the TARDIS). Release date is Jan 9th, so looks like they don’t want to pre-empt the Christmas Special. Last year’s trio were officially released on Boxing Day but there were plenty of advance copies around – I ordered from a book club and they arrived by December 10th.