Possible addition to the 4th rule

[JAWS-test]

The 4th rule says:

Do not use role="presentation" or aria-hidden="true" on a focusable element . Using either of these on a focusable element will result in some users focusing on 'nothing'.

For role=presentation this is not true according to the ARIA specification.

If an element with a role of presentation is focusable, or otherwise interactive, user agents MUST ignore the normal effect of the role and expose the element with implicit native semantics, in order to ensure that the element is both understandable and operable.

I'm for keeping the fourth rule, but changing the explanatory statement. role=presentation should not be used for focusable elements because currently many browser-AT combinations do not follow the ARIA specification (I tested it with NVDA and JAWS + IE 11, Chrome and Firefox for example and the results were very different) and because it would not be valid HTML code.