bounds of authoring tool responsibilities with respect to encouraging/checking/repair, etc.

My suggestion regarding B.2 is that the authoring tool is responsible 
for the authoring decisions the authoring tool supports.

This means with an HTML editor the decisions are what HTML elements 
will be used. For content management systems the decisions are which 
templates to use, what form of styling to use, what formats to 
support, what widgets and controls to include, etc.

Jutta