Neither me nor crut are picking nits here, it's a very important point to be aware of. General real world resistors are designed to be relativly linear through their voltage and wattage ratings. Lightbulbs are not. If you say a lightbulb is a resistor and then use one and expect it to be linear like a typical resistor you would be wrong. In this case you're correct it doesn't matter, but it isn't true for all cases so at least mentioning the non linearity thermal instability of lightbulbs is a good idea, which is what we did, not pick nits =)