fadeOut "disabled" by a seemingly benign line of CSS (jquery bug?)
===

This is a follow up to: 

http://stackoverflow.com/questions/11438556/fadeout-on-an-li-stops-working-after-using-addclass-on-div-that-wraps-the-ul

Now that I've scoped it down to a single line of CSS it seems like a good spot to reask the (now) correct question. 

This is the line of CSS:

.status-fullscreen .main-slides img.display-full {position:absolute; top:0; left:0; width:100%; z-index:350}

(btw, this "trick" comes from: http://css-tricks.com/perfect-full-page-background-image/ so it's seems pretty legit.)

Pseudo code it applies to:

    <div .status-fullscreen>
      <div .main-slides>
      <ul>
        <li><img .display-full /></li>
        <li><img .display-full /></li>
        <li><img .display-full /></li>
      </ul>
      </div>
    </div>

When the line of CSS is in play and I'm working the .go(index) of the list, fadeOut() stops working as expected. That is, it doesn't work at all. fadeIn works tho' the duration seems to be off. Remove the line and all is well. 

What gives?

I'm sure there's another way to produce fullscreen image. NBD. But it would be nice / helpful to understand what cause fadeOut to be eff'ed by what's in this line of CSS. Maybe it's not a bug but it does seem pretty damn odd, yes?