Firstly, they comment about the concept of Ciaccona. Ciaccona is a baroque term and therefore the difficulty for the student is playing in that pulse but maintaining Bartok's language.
In fact, the character should not be so light (as in the Baroque period) but more powerful and energic. Moreover, it should be as a "lament", "speaking" but without releasing tension.
Afterwards, they work on phrasing, notes duration, and accents issues according to the rhythmic pulse.