In Doctor Who S2Ep5 Rise of the Cybermen, the Doctor says that when galifrey and the Time Lords were around they could hop between dimensions without anything bad happening. In S4Ep13 Journey’s end, as a result of the Doctor metacrisis, a new ‘Doctor’ was created that was half time lord, half human. This Doctor would age and behave like a human. However because he killed the entire Dalek race he was exiled to another dimension with Rose. If the Galifrey and the Time Lords aren’t gone forever, and if they come back then surely the Doctor could just hop to another Dimension and the series could bring back David Tennant, as this new human/timelord character. Obviously they probably wouldn’t make him a permanent fixture, but it would be really cool to see him there for a few episodes, and it would also bring back Rose. It’s an idea, and I think it’s entirely possible, and it would be so awesome, having David Tennant back again for a bit.
