Am I right in understanding that Emma was actually sharing her opinions of Mr Churchill with Mr Knightley, but was arguing with him for fun? She then proceeded to say a good deal more than she felt, of the advantage of such an addition to their confined society in Surry; the pleasure of looking at some body new; the gala-day to Highbury entire, which the sight of him would have made; and ending with reflections on the Churchills again, found herself directly involved in a disagreement with Mr. Knightley; and, to her great amusement, perceived that she was taking the other side of the question from her real opinion, and making use of Mrs. Weston's arguments against herself. chp 18.

Does this mean that Emma does in fact think that Frank could visit his father should he really wish to?

"And mine," said Mr. Knightley warmly, "is, that if he turn out any thing like it, he will be the most insufferable fellow breathing! What! at three-and-twenty to be the king of his company -- the great man -- the practised politician, who is to read every body's character, and make every body's talents conduce to the display of his own superiority; to be dispensing his flatteries around, that he may make all appear like fools compared with himself! My dear Emma, your own good sense could not endure such a puppy when it came to the point."

and
"He is a person I never think of from one month's end to another," said Mr. Knightley, with a degree of vexation, which made Emma immediately talk of something else, though she could not comprehend why he should be angry.