This is somewhat of a test, but I went to my User CP and unchecked the “show signature” box in the Edit Options page, and save my settings. Even though on this Reply page, the “Show Signature” box is checked, my sig doesn’t show up when I post (though I do have one - I checked).
I don’t WANT my sig to show up, so that’s fine by me, but it might be good for those posters who don’t want their sigs to show up.
That “show signatures” thingy in the User CP is not to turn yours off, but rather it causes the board to not display anyone’s signatures while viewing. That’s why you can’t see yours anymore. You won’t see mine either, even though I’m including it.