Good point. In 16 years of working as an editor, I never used a WYSIWYG tool nor did I miss that – the text was written in Emacs (yes, we were that stubborn) and a custom-made mode applied basic formatting on the fly (italics, bold, headlines). More importantly, it highlighted “bad” words/grammar. The more colorful a text was, the more work it required.
I’d love to see that in DT, but I won’t hold my breath.