Re: Reminder: please check this text before the call.

LGTM.

But the part about `validate`, which is unchanged I think, is not clear.
The update done before the submission also revalidates data. The `validate`
attribute, when set to `true`, should just check that there are no invalid
nodes remaining, based on validity information computed during the update.
I don't think it should cause other validation steps to run again.

-Erik