I'm about to connect a new radiator to an existing central heating system and wondered what the merits of TBOE connection are compared to the usual method of connecting both inlet and outlet pipes to the bottom of the radiator. I don't care about the prettiness of the layout - just how it performs. In particular: Is the heat output improved by TBOE connection? Does the fact that the water flows diagonally make any difference to air pockets inside the radiator? Is it better to have the inlet at the upper or lower connection end? I've never seen TBOE in domestic installations - is there a reason (other than habit) for this?