Let me put what I'm trying to say differently.
Imagine that you're presenting an equation to an audience. Consider the following four ways that you might choose to present that equation:
1. You could write it out in front of them on a chalkboard;
2. You could type it into PP or some other display software, live, with the equation being displayed on a screen of some sort as you type it;
3. You could type it into PP or some other display software in advance, and have the equation slowly revealed to the audience as if it was being written out;
4. You could type it into PP or some other display software in advance, and simply have the equation presented immediately in its entirety (akin to the entirety of a PP slide being revealed at once).
With admittedly nothing but personal experience, and the experience of professional acquaintances, to base this on, I claim that these four approaches will differ in the (for lack of a better term) psychological response they obtain from the audience, that those differences have to do with fundamental characteristics of how human beings process their environment, that much of those differences have to do with the psychological perception that the presenter is creating the information being presented at the time the presentation is taking place, and as a result those differences have nothing really to do with the effective use of software.