Ryuji, I know how to measure ISO, EI and ASA speeds as well as several other methods you may never have heard of.
I have posted some valid results and have ISO 25 pictures to back up the results. I also have comparisons from Polaroid exposures. In addition, the wedge spectrograms were done with a fellow engineer present and were verified by him. These exposures were done a few months ago, and were only posted after I had accumulated all of the various pieces of comparison data.
If you have objections in the form of concrete data, you are free post your actual results. Pictures, wedge spectrograms or step wedge exposures would be appreciated. My pictures with step wedges are posted elsewhere.
I wish you the best.