The "five repeats" comes from page 238:
Unfortunately, the last 3 paragraphs referred to would be on page 237, which is not present in the Google book preview. This is like one of those "treasure hunt" movies...
Flipping a normal panel over 180 degrees and presenting the back face to use as an inverse, only works if the panel is made to the full design depth. This of course negates the 4/7 gain you get with an N7.