I just finished watching the director's cut of King Arthur and The Hole, both of which features Keira Knightley.
King Arthur claims to be "the untold true story that inspired the legend"--a claim which I doubt any well-educated person would have believed in the first place. Historical accuracies aside, they have very little evidence to make the definitive claim that the King Arthur of legends was a Roman centurion.
In the director's cut, they show the young Lancelot arrive to meet the young Arthur, with the both of them looking to be pre-teens, and then we skip to 15 years later, where we see Arthur as a... 40-year-old man...? Meanwhile, Lancelot is in his early 30's. They should have just made the thing 20 years later, instead of 15, if they were going to use actors who are so much older. I guess that might be why the scene didn't make theatrical cut... though I doubt it.
Overall, the movie itself was not too bad. The early battle scenes didn't need to be as long as they were, I thought; it was also shorter in the theatrical cut, but not for the reason of pacing.
I thought The Hole was a much better film than King Arthur... although I guess it's a bit unfair to compare two completely different types of film.