Using Humanoid:SetStateEnabled on the server does not replicate the change to the client. Changing the Dead state to false, for instance, and then using GetStateEnabled, will return false on the server and true on the client, or vice versa if SetStateEnabled is called from the client. It doesn’t replicate at all and that isn’t documented.
Would this mean that you’d have to call
Humanoid:SetStateEnabled(Enum.HumanoidStateType.Climbing, false) on both server and client to improve performance?