Yes, I see where you"re going. Just tried it. At 500 RPM it is nice and slow. At 900 it"s twice as fast. At 1200 it jumps.
When I"m plowing snow with a heavy V-plow, and the engine is at high speed, I lift and lower the plow at that speed. At least I hope to. Going through a 24-inch drift may require lifting the plow a bit, but when it jumps up, it seems as if it"s tearing things apart.
BTW: about plowing snow on a hilly lane: it has wheel weights and chains, but the poor little thing is so light, we just had the tires fluid filled. This also helps when pulling logs up a grassy slope. Fun little tractor.