I was camped along a river in a rain forest in Oregon and we collected quite a bit of quarter inch diameter firewood which my partner built into a teepee fire. He then used up 8 ounces of alcohol trying to light it. Perhaps due to his efforts, I was able to light the fire with my gigapower torch that I brought for the occasion. I used almost an entire bottle of fuel getting the fire started so I could cook steaks over it. It would have been far more efficient to have cooked in a pan.
I have used the torch to warm a titanium cup full of water for coffee, but you have to be careful not to burn yourself.
anyway - even a gigapower torch is not adequate to start a fire someplaces without an axe and chain saw to get to dry fuel. Its important to realise that its a waste of time to even try to start a fire someplaces - go to plan B.
I mentioned elsewhere about how to light a fire with a small gas stove. Its dangerous but effective. Perhaps using an esbit is about the best most effective method of getting some real heat rising through a pile of fuel. If you carry anything for fire lighting besides a lighter or matches, you may as well carry a couple of esbit instead. atleast on short trips.
These are my own opinions based on wisdom earned through many wrong decisions. Your mileage may vary.