Actually, Header IDs are page generated, and not optional.
Elements
How could be a new system, more element based. That way, users may set options during including, like :
%MAIN?headerid=1-3%
or %MAIN?headerid=0%
Or add the possibility to generate anchor links after titles.
%MAIN?headerlink=1%
ID style
-> sub headers
To avoid collision, headers ID could use this form : h1/h2/h3
. It could be very long depending of the deepness.
This should also be a rendering option. For example : %ASIDE?headerfamily=1%
Summary
Now, what about summary ? should it be element based as well ?
If so, for example, how to add a summary in the NAV
element, referring to the MAIN
element's headers.
%SUMMARY?element=main&range=1-4%
If think it is starting to be too complicated. If users can disable headers ID on elements they don't want, they can already manage to use only one element if they want.
Conclusion
So technically, the summary element, may stay page based, but the header IDs should be element based.