Is 12-13 minutes to much of an inconvenience to wait to boil half a litre of cold water?


All too often, yes. If I need to go to a wood fire, which does happen occasionally, I have always been able to boil water over an open campfire - cost and weight essentially nothing. This does presume conditions which prevail in western North America. I could believe that the situation is different on your side of the Pond.