I have to side in (tentatively) with Jeff on this one. If the rep spring is correctly tensioned, the action centers and key bushings at correct (appropriate) friction and the action otherwise regulated correctly... hammer rest cushions do little if anything to affect repetion. Indeed... the only way the cushion could get into this picture is on a blow where the shank actually does bounce off the cushion... which I think as Fred mentioned puts us in the Staccato. But on that kind of blow everything is released and there is no reason for the jack to jam if the afore mentioned conditions are in order. Very fast single key repetition doesn't really get into Staccato per sé... and I am unsure as to whether or not the rest cushion is actually contacted by the shank in those very fast single key trills. It would seem like an awfully long way for the hammer to have to travel back and forth should that be the case tho. This said... I wouldn't go so far as to say we shouldn't need the rest cushion. It does keep the rebounding hammer from over stressing other parts of the system by preventing excessive downward travel. But I am unconvinced it really gets into repetition issues so much. In any case I have never had a rep problem I couldn't resolve by addressing friction and regulation issues alone. Cheers RicB
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