In the end that is usually the motivation of the blocker. I've traded (or attempted it) several times. 90% answer and approve immediately, most of the rest are slow to answer but reluctantly approve, then there are the blockers. In my case going to the original Paris FDA. I had two blockers ironically one was a non-member and the other a Union offficer. Both sent me a message to call them as they had a 'great idea' to solve the trade problem. Their magic solution ended up being a three way trade to launch themselves into the slot I had traded for. In the end Paris was canceled so it didn't matter.