If caedes is serious about comments by users on new postings and the c-index, the present method has to be changed. I have suggested this before but no harm in trying again: Every user must vote on 10 posts and also comment on three or four before posting her/his own. Comments on postings of unknown authors are more likely to be impartial. I have noticed that even new-comers have quickly learned to join such groups of friends and now comment only on contributions of their "new friends". With the c-index it is the same problem. Friends have already seen the new posting of a friend and when they eventually get it in the voting booth they may not be so impartial.