Focusing on the “who, what, when, where, why, and how” words will slow your reading speed, but it will increase your ability to “understand and remember” the “answers to the questions words” in the paragraph you’re reading.
Reading slower will increase your ability to “understand and remember” the “answers to the questions words” and improve your comprehension of the text during your second reading.
In other words, your second reading will be more effective because it will be much more of a study session, just a second reading session.