After reading Maps of the Ancient Sea Kings: Evidence of Advanced Civilization in the Ice Age, I thought this book might clear up some issues and provide some analysis of previous studies done on this map. I feel that this book did a good job in this area. McIntosh goes to town on the sloppy methods used by others over the years and conducts a more unbiased study without putting forth wild theories or making the data fit any preconceived notions. His discussion about Piri Reis' use of a map made by Columbus is worth the read.
Here are a few quotes that I found apt in terms of criticizing earlier studies done. "It appears the method of Kahle, Levillier, Mallery, Hapgood, and others was to ignore the place-names inscribed on the landforms on the Piri Reis map, compare its features with a modern map to 'identify' the features, and then contrast the 'amazing accuracy' of the manuscript Piri Reis map with early printed maps." (pg. 41) Also on this page he notes that Hapgood only really looked at printed maps, which were "more inaccurate for their time", and that "the Piri Reis map is no more accurate than other manuscript maps of its time". McIntosh goes further in stating that "selective use of data can be used to support almost any untenable position". (pg. 68)