In which case, the @DOCUMENT binding method I suggested should work for you (if it makes sense).
I don’t think you need to worry about editing html. The content can be edited using TinyMCE so (in theory) the html doesn’t need to be touched by the admin/editor.
I realized that for this particular case that OpenGeek’s suggestion of Chunks would suit the situation perfectly (site-wide updates) - thanks! I have printed out bob1000’s documentation re: TVs, which will be very helpful to me - thanks, b1k!
But I’ve got a new "challenge" - I need to have (other) boxes in the sidebar filled according to the page they’re on, so their content would be page-specific.
All my pages use the same template. Is there some way to specify the TV should be applied to just one specific page? (I’ve had a look and it’s not immediately obvious...)