Thanks to the secret history of star wars a lot more people are realizing Lucas made things up as he went, and did not have a 9 movie outline and the whole story already planned out in the early seventies.
This is a lucas created myth and large piece of misinformation to explain away all the prequels inconsistencies.
Its not all that hard when he has direct control over all that is said about him in official Lucas publications, even when out of print Lucas publications contradict him like bantha tracks or once upon a galaxy.
Plus you have 2 sites to keep people in the dark tfn and starwars.com.