I tried the way that Ed talks about above (if i'm doing what your talking about right sorry if i'm not) but I don't always see the itrader (0) to even click on. Here is an example Homebrewdad started a thread called "Homebrewing myths that need to die" I see his join date, location, posts, and likes but i don't see an itrader (0) that i can even click on. Please correct me if I am doing this wrong.
https://www.homebrewtalk.com/f14/homebrewing-myths-need-die-400198/
Using my Technic I was able to figure out that homebrewdad's unique number is 105245. So this link would allow you to leave feedback for him:
https://www.homebrewtalk.com/itrader.php?u=105245