When members submit a request like, Please delete thread, with no justification then we most often ignore it. You need to provide a reason and a good one at that. Google archives this site so if it's an attempt to hide, the damage is already done and you're now a part of Google's history. But, we do end up following through with most requests for the sake of organization within the board and not covering up a member's goof-up.
All moderators can review each thread report, and I especially review every one to make sure something was done. So if it appears ignored, it wasn't. We either took care of it behind the scenes or the request was not warranted.