I think “when there’s a risk of losing traction” is the key to this whole issue. I agree with the original poster that using the cruise on wet roads isn’t inherently dangerous, but I disagree that if you start hydroplaning, you will have the presence of mind to tap the brake, apply the correct amount of throttle, apply the correct steering inputs, and save the car, all in the 1/4 of a second it takes for your car to start getting sideways. I don’t know if you’ve ever been in the situation, but let me tell you, it’s a lot harder to save a car that’s already going sideways, than it is to prevent it from going sideways in the first place. Momentum and inertia are funny things like that.