I started to try to explain it, but it's easier to just cut and paste the synopsis:
The Rangers' mission was clear. They were to lead the assault on Omaha Beach and break out inland. Simultaneously, other Ranger units would scale the cliffs at Pointe du Hoc to destroy the ostensibly huge gun battery there and thus protect the invasion fleet from being targeted. But was the Pointe du Hoc mission actually necessary? Why did the Allies plan and execute an attack on a gun battery that they knew in advance contained no field guns? And more importantly, why did they ignore the position at Maisy that did? Using personal interviews with the surviving Rangers who fought on the beach and at Pointe du Hoc, The Cover-Up at Omaha Beach presents exceptionally detailed new research that takes the reader into the middle of the action with the Rangers. Gary Sterne has made a painstaking study of what the Allies actually knew in advance of D-Day, including what was known about Maisy Battery. Maps, orders, and assault plans have been found in US, UK, and German archives, many of which have only been recently released after having been classified for more than sixty years. Radio communications of the Rangers as they advanced inland have been found, and Royal Air Force intelligence evaluations of bombing missions directed at the site have now been released. All these combine to make The Cover-Up at Omaha Beach one of the most up-to-date references on the subject.
I believe it took the rangers another 3 days or so to take the Maisy battery, (with more heavy casualties.) I saw it somewhere on a D-Day documentary. It was a giant massive battery that military intelligence initially overlooked and then totally covered up (thus hiding more Ranger sacrifices that were required to take it).
bump.