This post is about Revision 1.3792 dated February the 15th 2010.

my wonder is about the step 1 of the steps to be run by user agents for resetting the form owner of a form-associated element, described in section 4.10.16 :
"1. If the element's form owner is not null, and the element's form content attribute is not present, and the element's form owner is one of the ancestors of the element after the change to the ancestor chain, then do nothing, and abort these steps."
At first I thought it missed "the element's form owner is the nearest form ancestor of the element", but then realized that nesting form elements wasn't conforming to begin with.

Yet now I'm confused : should nested forms be considered just not conforming and omitted in the above-mentioned algorithm? And if so, why bother to define the default form owner as the "nearest ancestor form element" at the top of the section.
Should form elements be considered potentially nested, or not ?

Unless I'm mistaken, I believe there are situations (consecutive scripted ancestor changes) where this first step would allow a form-associated element to remain associated with a form owner which is actually not its nearest ancestor form element... And no form content attribute to reflect or correct this. If so it could lead to cases where there's no certainty about which form an element is associated with.

On the overall, I find the "nearest ancestor" versus "forms can't be nested" duality is made rather unclear in the section, and I leave it to more competent people to sort it out, or see if there's anything to sort out.