and therein lies the debate... I left them out under the rationale that the water would flow through the block and the radiator quicker.
ultimately what happened was the carrier would take a lifetime to heat up, but once warm would be fine for a while, would get hot in the end though, mind during tear down I found my block was full of sediment, so that would perhaps explain that.
is there a definitive answer to this question, or is it yet another unsolved mystery of what is better...
chicken or egg ?
I am running a bespoke Aluminium radiator which may come into play as I doubt it will free flow the same as the old brass item.