To be honest I am not agree with demerit system. I don't believe that merit could be send by mistake. It's not same as Facebook like that could be press by mistake. During meriting time there is new tab, that means you are fully aware that you are going to merit someone. On the other hand once you are meriting someone you are meriting on post, you are not consider a person. Same thing for others people also. Say someone merited me on a post,  but in case after few days if they aren't agree with me for any reason than may be some one will think I will demerit my merit. It's just example, but I think it would be happen. I don't think it will be fair.

If you think for source of demerit like current merit source than also I am not agree. You will se many accusation against them. Adding demerit source means merit will moderated by forum. So it would be easy to question forum. And it's more difficult to identify who are really abusing. Without proper explanation couldn't be demerited. You can see sometimes there is accusation also against merit source regarding merit abuse. So you can imagine how many accusation will be against demerit source.

For me current merit system is working fine. Just we need to follow who are abusing merit system and identify them for tag. I know merit abusing increase after implement new rules. But I don't think it will longer as well they are getting red tag if caught.