Brucey wrote:.................I also had another look at my collection of worn brake blocks. I'm now thinking that at least some of the issues have been with the OE BR-AT50 shoes which are maybe simply not strong enough; I reckon the holder can distort near where the post attaches................
Should be pretty easy to either prove or disprove, just by swapping shoes between brakes? And it would be one tiny step to a better understanding!