>>514190My video that I posted above shows the importance of having a good windscreen. Normally the flame jets form a perfectly symmetrical pattern around the kettle but the slightest breeze disrupts this causing the flames to dance around and get blown to the side where much of the heat is actually missing the kettle and being wasted. Pictured is the windscreen I use with this particular stove. It's made from a roll of aluminum flashing and works pretty good but really needs to be slightly taller.
The plastic measuring cup in the vid holds 20ml of fuel (1oz = 32ml). I normally use 60 ml (about 2 oz) of fuel to boil 750 ml (roughly 24 oz) of water. Sometimes this isn't hardly enough fuel due to many different factors such as the temperature of the water, the amount of wind, the shape and size of my boiling vessel, the outside temperature etc. etc. When this happens, I just quickly dump in another 20 ml of fuel and that's usually more than enough to bring it to a boil.