I don't know if this issue already in WordPress idea. As a developer I'm quite familiar with HTML Syntax and I don't have any trouble to use HTML Editor to post. WYSIWYG Editor is very annoying. I use syntax highlight in some posts and the post will be broken in WYSIWYG editor. But I'm sure still there are many people don't know about HTML and its syntax. WYSIWYG Editor is helpful for this kind WordPress User. For me in some case,
I want to suggest in the next WordPress version :
There's an option to choose what kind editor should be used for a post, when we create a new post. This option must be saved in database with the post. Maybe in wp_post table there's a flag field. If the flag value 'H' then the post will be opened in HTML Editor, otherwise (maybe the value is 'W') the post will be opened in WYSIWYG Editor.