I posted the issue 8792 and now, reading it one more time, I understand I was not clear at all. I am sorry for this.
Let me try again... and maybe at the end you will answer me that I am still not understanding the provided solution.
As shown in the page http://test.moodle.com/course/view.php?id=5 almost each item of the argument one moves the user to a page
-> with: breadcrumb
-> with: the embedded resource
-> without: frameset
What I reported is not true for .mpg and .swf.
As it is possible to write an accessible compliant page embedding swf (http://test.robertoellero.it/elaborazioni_sottotitoli/index.htm, http://test.robertoellero.it/elaborazioni_sottotitoli/captioning_flash1.htm, http://test.robertoellero.it/elaborazioni_sottotitoli/captioning_flash2.htm), my question is: if moodle doesn't change the way to serve pages for swf and mpg resources, this is a break in the XHTML strict.