From post and comment thread here: http://css-tricks.com/navigation-in-lists-to-be-or-not-to-be/
Probably good with just "You can't role=navigation on a "
"Verbosity in screen readers is a choice" seems more like a draw.
Maybe it could read "More verbose in screen readers", or get combined with "Announcing the number of items in the list can be helpful"
"The spec doesn't care" also seems like a draw.
fair points, will adjust
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