GMAT Sentence Correction (SC) | Re: Biographer David McCullough presented an in-depth study of Harry S. Tr

Hi Mike ,

In the example of the sentence you cited "What the eye sees, if it is at all different from what the brain visually perceives, then this distinction is, for practice purposes, meaningless."

the correct option you have cited , "The distinction of what the eye sees from what the brain visually perceives is, for all practical purposes, meaningless." , does this not change the meaning of the sentence ?
The original sentence says that as a possibility , uses if , the