Derek Wright wrote:
So, hypothetically, the updates from 4.6.x to 4.7.x might have used some function in 4.7.x core that no longer exists or works the same way in 6.x. If that was true, you couldn't just upgrade directly from 4.6.x to 6.x, since when you hit the update function that only worked in 4.7.x core, it would fail and then the rest of the upgrade path could be busted. Therefore, first upgrading from 4.6.x to 4.7.x, then from 4.7.x to 5.x, and finally from 5.x to 6.x, is the safest, since you're always running update functions against the version of core they were written for and tested with.
There was exactly a node types API problem with updates from Drupal 4.6 to 5.0 going directly: http://drupal.hu/english/node/8 Gabor