Reading the books and knowing what to ask is one thing but practicing with a study partner is another thing. It involves recall of questions, time efficiency and ofcourse dealing with another individual who can pose to be a challenging SP.
Watch this :https://www.youtube.com/watch?v=zyLXgRMohYY
Online study partners are convenient - to travel , can study at odd hours and is safe. However for live interaction, communication skills, draping, washing hands, examining all of which take up time a live practice is more ideal.