Gee, Gordon, no offense, but I'm thinking old wives tale. I'm reading that Wade and most of this list would agree that back porch/chassis weight does not contribute to bearing failure. Case in point: Since 1991 my Elec-Trak (160 lbs at the back porch), 240 lbs in four batteries, 80 lbs transaxle, electric lift made the plow up/down/left/right a breeze. No fluid in tires, no annoying wheel weights. I miss it the ET. No plow for my CC102. Craigslist North Jersey has my CC listing where you'll find a rear weight kit, never installed it on the Cub.Remember that weights attached to the chassis translates to weight on the wheel bearings ( or bushings in most cases and you may want to rethink that as the bushings are small and soft metal. Wheel weights ( including filling the tubes halfway with water does a marvelous job of creating traction weight and stability on slopes.
I know there is that cracker picture with 20 wheel weights on each side and Im not 'for a moment suggesting you all go completely bonkers, but a double pair of wheel weights inside and out plus water should give you plenty of traction, also allow the tyres to bulge a bit by not pumping too hard.
remember that every action has an equal and opposite reaction, so those poor bushings are not going to thank you for extra chassis held weight
Best, Jack