Yes the PhotoReading system includes the effective reading techniques developed from research. Using those steps alone will improve the results obtained by many in reading.
However people who have had to resort to the PhotoReading step alone because their other commitments didn't give them time to do the other steps. And then passed exams based on the knowledge they got from PhotoReading alone won't agree with you that flipping pages has little value.
For others the difference in understanding the information is worth the 2 to 5 minutes of flipping pages.
Alex