Theory:Doctor Who television discontinuity and plot holes/Warriors' Gate


 * When the Doctor says his farewells to Romana he gives her K-9 without strain. In A Girl's Best Friend Sarah Jane found it hard to lift K-9 as he was very very heavy but Romana manages to carry his weight like a toy.
 * It's not the same K-9, and Gallifreyan strength has no been advertised much.