If your luggage is being checked straight through from TFS to the final destination then you may be transferred directly to the departure lounge on arrival at Dublin, meaning you can not got back through passport control as you will actually bypass it in the first place.
If its another airline company you're travelling with and you have to physically check back in when you arrive at Dublin, you're free to do what every you want. But you will have your cases with you so if you can check them in early fine if not..bugger!