In chapter 7, we get a description of Edmund's visits to the Parsonage to hear Mary play the harp:

The harp arrived, and rather added to her beauty, wit, and good–humour; for she played with the greatest obligingness, with an expression and taste which were peculiarly becoming, and there was something clever to be said at the close of every air.

First, there's this "there was always something clever to say". How annoying! Whatever Mary does, she must say something witty, she must exhibit her quick and "lively mind"! And we've already seen (her remarks about the Admiral), she would rather be tactless and tasteless than silent. Anyway, this passage always makes me angry with her.

And the second thing is, it does not actually say that Mary plays well! She is "obliging", has "expression and taste", and of course, she is clever. But, how well does she really play?