Hello to the drupal team,

thank's for your work first!

I had to notice a side effect that is caused by design and should be mention in documentation, I think.

When an admin alters the node filter to one that the node owner has no rights for, the node owner can't edit the node any more.

This makes sense in any respect but is somehow a surprising moment and you'll take some time to get it. It would be great to print a notice with the node that edit was disabled due to an improper input format filter set to the owner of the node.

An example, the author doesn't have the rights to select "Full HTML" but is asking the admin to set this because hte content needs it. If the admin does change the filter the author is no more able to alter the content of the node.