Extension levels

Hi all,

Another topic that we would like your input on is 'Extension Levels'. 
You can see the minutes from this topic here, as well as the current 
survey. [1] [2]

We asked the group if extensions should have 'levels' similar to current 
WCAG SCs. We asked "Specifically related to the conformance structure, 
what approach do you believe best?" The current answers/results to this 
question are:

Extensions should have levels    4
Extensions should assume a WCAG 2.0 AA base    8
Conformance claims for extensions should have the same level as the 
page's WCAG 2.0 conformance claim    2

So the majority are in favour of a WCAG 2.0 AA base for extensions.

Assuming then that the group are in favour of levels for extensions, 
then some options to consider are:

1) All extensions would be at a single particular level (AA).
2) Extension levels would map to the conformance claim level.
3) A higher level claim could map to/include a lower level extension, 
but a lower level extension could not map to/ include a higher level 
extension.
4) You can only make any extension claim when you have achieved a AA 
level of conformance.

What do you think?

[1] http://www.w3.org/2015/10/13-wai-wcag-minutes.html
[2] https://www.w3.org/2002/09/wbs/35422/extension_req/
-- 
Joshue O Connor/Andrew Kirkpatrick
WCAG working group co-chairs