I did exactly that for the third oven I built. It worked, but in practice I rarely used it. Having air enter the oven at the front then combusting around the dome, turning the flame 180 degrees before it exits, produces better circulation than entering from the back and jumping straight to the flue. The better system is to have the flue outside the oven chamber so the flue gallery is totally isolated from the chamber when the door is closed. A plug and port at the rear of the oven needs to be really well sealed or cold air will enter there. Because of contraction I found my plug would jam when the oven cooled around it. The flue at the front with flue gallery independent of oven chamber has proved to be the best design and used for centuries. In 2 thousand years design alterations and different configurations must have been tried by thousands, yet this design remains,why? Because it’s been proved to be superior than any other.