[VE][html5] Warning about multiple h1 seems to go against HTML5 design

Validating http://www.echtrees.org.uk/2016/about/history/

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of the content.

I have a number of pages with a <section> which contains a number of
<section> groups.  Both the top level section and the subsidiary
sections have h1 elements.  This I understood is the suggested way of
doing things in HTML5.

However,  the validator gives me the following warning for the second
level h1's.

Consider using the h1 element as a top-level heading only (all h1
elements are treated as top-level headings by many screen readers and
other tools


Regards


Tony