Seems a bit useless, as just getting more and better armour is just as usefull up to 50% of the damage dealt. Depending on when the Damage reduction from timber-wise is applied it might even be bad. If the reduction is applied after armour it will be very bad, and prior to armour it will be useful, but not to the point where i would recommend it to someone over the straight up armour buff from another runestone.