Addressing difficult subject matters
You might be talking about a subject that's very personal to you that's going to cost you a lot to talk about, and it might be quite emotional.
So those moments you need to prepare very carefully so that you're coming at it from a point of control.
Speak from the heart, but don't fake the emotion. Otherwise, no one will believe you, but it's important to be controlled. It's almost always not effective to burst into tears in the middle of a presentation. A great actor once told me it's not important that you cry on the stage.
What is important, is that the audience cries.
So what that shows you, it's about the effect you have on your audience.
But it must be, it must be authentic. It must be heartfelt. If yes, immediately you try and fake it. The audience will spot that straight away and they won't believe you.