A potential problem with this approach would be competition: posters who are desperately looking for a job will keep trying to one-up each other with their accomplishments, and it could get ugly.
I put "No recruiters" on every single section of my LinkedIn profile, yet they still e-mailed. Eventually I removed every single detail from it. Even now I get the odd message.
They get a significant portion(10% or more) of your first years salary if you get hired. It's a numbers game and the more people they call the more money they make. They have a thick skin and the only thing stopping them from that money is a brief no from you. They will definitely try.
