Re: What happened to 'time travel at will'/slingshotting?
The difference is in the history.
History recorded the Ent-C was lost at the Battle of Narendra III
History recorded the Bozeman was simply lost presumed destroyed
On the continent of wild endeavour in the mountains of solace and solitude there stood the citadel of the time lords, the oldest and most mighty race in the universe looking down on the galaxies below sworn never to interfere only to watch.