Controls inside fieldset[disabled]>legend:first-child styled disabled

Created by: darobin

As per HTML5, controls inside the legend first child of a disabled fieldset are not disabled. This is not a random decision and addresses notably the use case of having a radio or checkbox control in the fieldset, as part of the legend, deciding whether that fieldset is enabled or not. Fiddle: http://jsfiddle.net/tyVF4/2/.

I headed for the source to fix that, but then I saw this comment:

// Note: HTML5 says that controls under a fieldset > legend:first-child won't
// be disabled if the fieldset is disabled. Due to implementation difficulty,
// we don't honor that edge case; we style them as disabled anyway.

Is fixing this issue completely out of the question? If not, could you be more specific about "implementation difficulty" before I foolishly jump into it? Right now I'm overriding this with cursor: auto.