TinyMCE apparently implements table editing using the insertHTML command (if you break on
JSEditor::execCommand you'll see this.
Created attachment 6771 [details]
implements insertHTML and patches editing.js to test it
Comment on attachment 6771 [details]
I would suggest adding another test that wouldn't be passed by a version of the command that does nothing (the current test would be passed by a no-op I think).