I hope you're all having a good start to the new year, and best wishes for the rest of 2019. I understand that a high phosphorus content in cast iron brake blocks improves braking, as well as giving a longer life as it increases the hardness. I need to learn if high-phos brake blocks are suitable for use with newly-turned (hence relatively soft) tyres. Or should low-phos iron be used for 'running in', to give the tyres time to work-harden? Any help very much appreciated, as always.