Be it hereby declared: laying the absurdly heavy cast-iron grates from the stove on sawhorses in the driveway and pressure-washing them produces a dramatic improvement:

They’re now devoid of the oil / grease / carbon accumulated during their decade of existence, little of which can be removed by hand; the shiny spots on the front right shrug off all solvents in my armory. The black finish still has plenty of scrapes & scuffs, but it’s no longer annoying.
You might think Samsung stove grates would fit in a Samsung dishwasher, but they’re too big and too heavy.
Also for the record: cyanoacrylate adhesive works wonderfully well to hold their little rubber feet in place.
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