Operation Fortitude: A Distraction for the 1944 D-Day Landings

Operation Fortitude was a military disinformation tactic designed to mislead the German occupiers about the date and location of the landings in occupied France on June 6, 1944. How successful was the operation?

Dummy landing craft, used during Fortitude, at an unknown location in the South-East of England
Dummy landing craft, used during Fortitude, at an unknown location in the South-East of England