Do CS Return Scrolls preserve slot if scroll fails?

I'm thinking about trying to get a few Return scrolls as an alternative to Shield scrolls.
The Description reads:

When applied to a piece of equipment which then has an upgrade scroll successfully applied, the Return Scroll allows you to decide whether you want to keep the new stats or revert back to the original state (including the upgrade slots). This is useful with Chaos scrolls, where a successful scroll attempt may still result in worse stats than you had before. Additionally, the in the result of a failed scroll, the Return Scroll acts like a Shield Scroll, protecting an item's upgrade count. The Return Scroll will not protect an item from being destroyed by a failed scroll.

However there seems to be some people who don't think the return scroll will save the slot if the scroll fails:

...when I used a return scroll a friend gifted me to use on his equip, when the scroll failed, nothing happened, slot was still lost.

Must be glitched then, i did not obtain my slot back on a failed chaos scroll of goodness.

But some others do think it saves the slot:

Just to note, return scrolls DO save slots from fails. I've never used them, but there's a youtube video of a guy using them while chaosing his tyrant belt. A lot failed for him, no slots lost.

So which is it? Do these preserve slot count if the scroll fails, or not? Or maybe they used to preserve slots when they were first released, but not recently.
Hoping that someone who uses these regularly and recently can give a definite answer.

Return Scrolls do preserve the slot if the scroll fails. They do not preserve the scroll though.

They keep the slot if the scroll fails but if the scroll has a boom effect it will still trigger that effect.

Proof: http://www.youtube.com/watch?feature=pla...QSc8#t=556 (9:10 or so)