I wondered if Tester had pronounced on this. "Assuming a symmetrical BB, this means a chainline moved inboard 1mm if you replace a 110mm JIS BB with a 110mm ISO one." - i.e. you are going from the top right diagram to the bottom left diagram, or from bottom right to top left. I think my diagram is consistent with what he is saying, though I need to revise it if it is true that the end of the taper is the same across ISO and BB, as in my diagram I have made the base of the taper the same. I made the diagram to help me get my head around the difference between the two standards, based on the observation that they both have the same taper angle. Anyway, thanks for pointing out the Testerism.