what is it about BP debating that makes students sway and rock while speaking?

I still don't get it. Is it the method of debating or the wrong training students are getting which makes them eat the words, speak too fast, sway and rock while speaking which I see rampant among those using the parliamentary style of debating? The skills or the manner is not there---poor audience contact, weak voice/delivery, rocking and swaying---what is that? There is too much haste in the delivery and the message, if there is any, is either lost in the effort or not understood at all. Students spend so much time and effort learning the wrong skills. In the end, it turns out to be a futile exercise teaching students the incorrect way by focusing only on the technicalities or format of the debate and neglecting to lay the important foundation of good public speaking or effective delivery which should be the end goal of all types of debate.