No way to force accessiblity here - just have to lead the horses to water and hope they drink!
Our distribution adds or configures the following:
CKEditor accessibility checking tool - for checking basic problems
Hiding H1 tag from the Formats drop-down list
Adding Font Size drop-down with sizes in percentages (80% to 150%)
A locally written module to display an accessiblity information panel on every editing page
- Lists most common content related rules in an accordion format for easy access
- Links to full Accessiblity Primer and Georgia Tech Editorial Style Guide