Oh, yeah, I found that one of them is in my ignore list.
Ignore and don't forget to report if you have time.
Economics is full of their threads, I remembered one day maybe that was last december or november, found most of the recent threads on economics are made by them both, like most of them.
My surprise is their threads attract many posters to join and 'discuss'. Earlier, I did not notice anything, and join discussions too but later on, when I found that those topics are from topic spammers, I ignore them.
I considered it as spam topics as too many topics were created per day or in a few days, and topic authors simply created topic and open it for discussions and abandoned it (lock button were not used).
Honestly, it is too easy to scan around and leave comments but in the past 2 or 3 months, it takes me more time to find good topics to join discussions. This step takes me more time than what I spent for my posts (sometimes).