From my experience, the reason for allowing the fuel mixture to soak in, is simply so that it will actually sustain the fire long enough to ignite the burn pile. I have previously used a liquid fuel mixture as a burn pile starter, but had the fuel burn off upon ignition, without actually leaving enough heat to sustain a fire in the brush - 'flash in the pan. Very cautious experimentation is a good idea. Exercise ultimate respect for the hazard of fire, including wearing only natural material clothing - no nylon!