Bumpy ice and slush require different strategies. Bumpy rutted tracks require fat soft tires and slush s best tackled with a narrow high pressure tire. Fat soft tires act as suspension to absorb the small bumps, but narrow high-ressure tires will cut through the zero-traction slush and contact the solid ground underneath.
FWIW, what they call in Edmonton “brown sugar” I call “ mashed potatoes”