How to hide the comment form label (not title)?
You can easily do this with CSS. Looking at dev tools, I see that the label is called edit-comment-body-und-0-value (yours might be different). So what we need to do is, simply edit the CSS file and put in the line label[for*="edit-comment-body-und-"] { display:none; } and clear the cache at /admin/config/development/performance.

That's all there is to it.

K.