I've been searching the codex, and I'm probably overlooking something somewhere, but could someone tell if it would be possible to remove a button/quicktag from the WordPress html editor?
The default is:
Edit to add:
If you wish to create a custom button the following tutorial might help.
I'm late to this party I know, but might I add that it's better to be agnostic about the default buttons provided by Wordpress. So instead of typing the buttons you want, I choose to remove the buttons I don't want:
Now if anyone at Wordpress decides the quicktags-toolbar gets a new button, it will show up in your editor without a code change of your plugin/function.