re: The End of Time (pts 1&2): Final DT episodes
On the falling issue - the presumption was that because the Master was using his "lifeforce" to almost fly in the first episode, that the Doctor therefore did something similar to slow his own fall to be survivable without using up too much lifeforce.
But as Dave pointed out much earlier, it was a fall of a couple of storeys from a satellite dish that killed Tom Baker's incarnation!
On the falling issue - the presumption was that because the Master was using his "lifeforce" to almost fly in the first episode, that the Doctor therefore did something similar to slow his own fall to be survivable without using up too much lifeforce.
But as Dave pointed out much earlier, it was a fall of a couple of storeys from a satellite dish that killed Tom Baker's incarnation!