Ok, here's the Link to a Posting where you see two sorts of downvotet comments, the second one is what I've talking about.
https://steemit.com/deutsch/@meins0815/wie-ernst-isses-denn
See the lowest comments under "beerlover". The first one is a downvotet comment which a Bot made and there's to read "reveal comment", so you just to have to click there and the comment is visible again as you've said.
By the comment below this is to read "Comments were hidden due to low ratings." I tried to click the button on the right where stands SHOW, but the comment was invisible furthermore, just the Button changed his inscription from SHOW to HIDE, that's all and that's what I've meant.
When you click that "show" button a new comment appears (by cleverbot), but for some reason it shows that at the very top, might be confusing.
Yes it is, but it's good to know I'm not the only one who was confused by this.
I'm glad a hard Censorship isn't possible here, because I heard it for some years and this was my main reason to come to Steemit.
Even if Steemit would hide comments completely, there are multiple other frontends (for example the eSteem mobile app) that still show them. ESteem doesn't even hide them behind a button.