Mr. Hanssing, these are all very fair points, but all points covered in Mod 1 - at least in principle. The devil seems to be in the execution. In the oxygen consumption poll on
http://www.rebreatherworld.com/gener...er-minute.html
plenty of trained ranks appear to be running consumption rates of 2 litres/ min, while some claim to be below 1. I would be willing to bet that they are all aware of the points you make and attempt to implement them. What do people who use less than 1 litre think they do differently?