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Tom
You just repeated what I said. Wattage rating has nothing to do with terminal temperature. Thermal resistance does. For example, modern metal film 1W and 2W resistors are smaller than older 1/2W carbon comp resistors because they are designed to run hotter (better materials) and do run hotter because they are smaller (higher thermal resistance). So in this case, a physically smaller resistor is a better choice for reliability even though it will run hotter at the same power dissipation as the larger 1/2W comp resistor.
If you want to state that a higher wattage resistor that is the same composition and much larger in physical size will run cooler, that is a true statement, but only because its thermal resistance is lower, not because its wattage is higher. The two are not absolutely related or interchangeable.
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