Adletson, I feel that it is less about looking for something specific in terms of bubbles and more about getting it right once and then trying to hit the same level of bubble formation. For example, if I defined the length of my arm as a new unit, wahooArmLengths, I couldn't tell anybody anything useful by measuring in wahooArmLengths, but the unit itself is consistent. If I wanted to draw something of some certain length, and through trial and error I find that length to be 2 wahooArmLengths, I can use that unit effectively by drawing it 2 wahooArmLengths every time even though others still cannot use the unit. I don't think that you need to use a 'unit' that others can convert to, just be consistent. Sorry for a long-winded way of expressing a simple thought.