I regard the ability to make fire critical, especially in heavy weather. But circumstances change - there are several instances of major forest fires started as distress signals, etc., and there are times and places where a fire is definitely not warranted. It is very unlikely that I would ever light even a campfire on any of the Channel Islands (SOCAL).That is a place where a signal mirror really shines (!).

When the forecast is for heavy weather, skip the bush craft routine and carry some sort of petroleum/alcohol fueled stove. they are well worth the additional weight and can easily be life saving. I've got the war stories to make that point....