Originally Posted by newflyer27

a friend of mine who started recently going to DUS quite often for work for 1 or 2 days max uses this "trick" often and takes the return instead of one way. He comes back with train sometimes or another return flight. He even call the elite line and asks for tax refund and he gets it without any problem. I was surprised. I actually told him before this that he should not ask for tax refund not to alert them he is doing this but he did it 4 times this month already and got 20 euros back from each flight (100 euros return ticket).