It just brings us back to how refreshingly simple and trouble-free it is to put a filter in the return line.
Difficult to know how much difference a filter makes to sludge trap filling, as particles of carbon black will pass through the paper element and will be trapped in the crankshaft.
Spanish Barrieros/Dodge lorries had a dinky little centrifugal trap, spun by oil jets, on the Hero’s jet engine principle.