Barna use examples most effectively in those three authors. The examples given by Barna are easy to understand and appropriate to support her arguments.
However, Fisher's examples are sometimes subjective. He gives many clear visual examples, but other examples are often based on his own experience. Using authors own experiences many times are possible to be thought subjective by readers, and weaken the evidence of the essay.
On the other hand, McDaniel's examples are little hard to understand. He gives examples only in a few sentences and uses some difficult words in it. Since it is academic writing, it is necessary to use formal words. However, roles of examples are not only proving, but make the argument more clear and easer to understand. I think that authors should use easer and more familiar words when they give examples.
Thus we should pay attention to sources of examples and way of writing.
By the way, I think the biggest problem for most of us is the amount of reading.
Do you know how many pages must we read in Shipman's article (No.12)?
28 pages! I am crying right now because of our unavoidable reality......
