This area sits in the same cold-severe climate band as the rest of the territory, and that's what actually breaks a torsion spring - not the lift cycles so much as the metal fatigue that cold makes worse. A spring that's been flexing fine all fall will go on the first hard freeze morning.
The usual sign is a door that won't budge, or one that the opener tries to lift and then reverses on, straining against weight it used to handle. Sometimes it's a loud bang from the garage first - that's the spring itself letting go, not the door falling.
With roughly 9,607 households in Chanhassen, a lot of them built in that same early-90s wave, we see the same pattern repeat: original pair of springs, same age, failing within a season or two of each other. If one side just broke, expect a call about the other side before long.