I can see both sides of this argument, and I think much of the conflict arises from a poor choice of wording on the card.

If it read "and may perform an attack", it would instantly make the rule much more flexible, giving the knight the option of utilising it simply as a means if movement.

I think sometimes rules are written assuming a openness to interpretation, without wording them loosely enough.

Thematically, why wouldn't the Knight charge forward to cover ground just because she can't attack afterwards? She is still capable of running isn't she?