The first concern would be the type of mug you cooked in. Was it thick or double walled? I too have the Crux Lite but will be cooking in a Bugaboo backpacker pot which seems to be thin walled and likely to conduct heat pretty effectively. Also, cooking in a breezy location will KILL the effectiveness of your stove. Heat losses through convection around the sides and top of the container can put your stove at a significant disadvantage. When we use pack stoves we try to do so with some sort of barrier to cut down on breeze coming through. We usually look for a downed log or rock outcropping where we can be sure we have a durable wind break.